Rules for illustrating patent drawings for China filing should be based on "Rules for the Implementation of the Patent Law of the People's Republic of China"
Below are the important articles related to illustrating patent drawings.
 

Article 17

•  The description of an application for a patent for invention or a patent for utility model shall state the title of the invention or utility model, which shall be the same as it appears in the request. The description shall include the following:

• ....

• (4) explanatory notes of drawings: briefly describing each figure in the drawings, if any; and

• (5) mode of carrying out the invention or utility model: describing in detail the optimally selected mode contemplated by the applicant for carrying out the invention or utility model; where appropriate, this shall be done in terms of examples, and with reference to the drawings, if any.

• ....

• The description of an application for a patent for a utility model shall include the drawings showing the shape, structure or their combination of the product for which protection is sought.

​

​

Article 18

• The drawings of an invention or utility model shall be numbered and arranged in numerical order consecutively as “Figure 1, Figure 2, …”.

• Reference signs not mentioned in the text of the description of the invention or utility model shall not appear in the drawings, and reference signs not included in the drawings shall not be referred to in the text of the description. Reference signs for the same composite part shall be used consistently throughout the application document.

• The drawings shall not contain any other explanatory notes, except for words that are indispensable.

​

Article 19

• The scientific and technical terms used in the claims shall be consistent with those used in the description, and the claims may contain chemical or mathematical formulae but no drawings. They shall not, except where absolutely necessary, contain such references to the description or drawings as: “as described in part… of the description”, or “as illustrated in Figure… of the drawings”.

• The technical features mentioned in the claims may, in order to facilitate understanding of the claims, make reference to the corresponding reference signs in the drawings of the description, and such reference signs shall follow the corresponding technical features and be placed in parentheses. The reference signs shall not be construed as limiting the claims.

​

​

Article 23

The abstract of the description may contain the chemical formula which best characterizes the invention; in an application for a patent that contains drawings, the applicant shall provide a figure which best characterizes the technical features of the invention or utility model. The scale and the distinctness of the figure shall be as such that a reproduction with a linear reduction in size to 4cm × 6cm would still enable all details to be clearly distinguished. The text of the abstract shall contain not more than 300 words. There shall be no commercial advertising in the abstract.

​

​

Article 27

• Where an applicant seeks the protection of colours, drawings or photographs in colour shall be submitted.

• The applicant shall, in respect of the subject matter of the product incorporating the design which is in need of protection, submit the relevant drawings or photographs.

​

​

Article 28

The brief explanation of a design shall indicate the title and use of the product incorporating the design and the essential feature of the design, and designate a drawing or photograph which best shows the essential feature of the design. Where the view of the product incorporating the design is omitted or where concurrent protection of colours is sought, this shall be indicated in the brief explanation.

​

​

Article 31

....

Where an applicant claims a right of foreign priority for his or its application for a patent for a design, and no brief explanation of the design was contained in the earlier application, he or it shall not be adversely affected for enjoying the right of priority if the brief explanation submitted by the applicant in accordance with the provisions of Article 28 of these Rules does not go beyond the scope as shown in the drawings or photographs of the earlier application.

....

​

​

Article 35

....

Where two or more designs are filed as one application, they shall be numbered consecutively and the numbers shall precede the titles of the drawings or photographs of the product incorporating the design.

....

​

​

Article 38

Upon the receipt of an application for a patent for invention or utility model consisting of a request, a description (drawings must be included in an application for a utility model) and one or more claims, or an application for a patent for a design consisting of a request, one or more drawings or photographs showing the design and a brief explanation, the patent administration department of the State Council shall accord the date of filing, issue a filing number, and notify the applicant.

​

 

Article 39

In any of the following circumstances, the patent administration department of the State Council shall refuse to accept the application and notify the applicant accordingly:

(1) where the application for a patent for invention or utility model does not contain a request, a description (the description of a utility model does not contain drawings) or claims, or the application for a patent for design does not contain a request, drawings or photographs, or a brief explanation;

​

​

Article 40

Where there are explanatory notes to the drawings in a description, but the drawings or part of the drawings are omitted, the applicant shall, within the time limit specified by the patent administration department of the State Council, either furnish the drawings or make a declaration for the deletion of the explanatory notes to the drawings. If the drawings are submitted by the applicant at a later date, the date of their submission or mailing to the patent administration department of the State Council shall be the date of filing of the application; if the explanatory notes to the drawings are deleted, the initial date of filing shall be retained.

​

​

Article 52

When any amendment is made to the description or the claims in an application for a patent for invention or utility model, a replacement sheet in prescribed form shall be submitted, unless the amendment concerns only the alteration, insertion or deletion of a few words. Where an amendment to the drawings or photographs of an application for a patent for design is made, a replacement sheet shall be submitted as prescribed.

​

​

Article 69

The patentee for a patent for invention or utility model concerned shall not amend his or its description or drawings, and the patentee for a patent for design concerned shall not amend his or its drawings, photographs or the brief explanation of the design.

​

​

Article 104 

Where the applicant goes through the formalities for entering the Chinese national phase in accordance with the provisions of Article 103 of these Rules, he or it shall meet the following requirements:

(5) where an international application is filed in a foreign language, submitting the Chinese translation of the abstract and submitting a copy of the drawings and a copy of the drawing of the abstract if there are drawings and the drawing of the abstract, in which the text matter of the drawings, if any, shall be replaced by the corresponding text matter in Chinese; where the international application is filed in Chinese, submitting a copy of the abstract and a copy of the drawing of the abstract which are contained in the documents of the international publication;

​

​

Article 113

Where the applicant finds that there are mistakes in the Chinese translation of the description, the claims or the text matter in the drawings as submitted, he or it may correct the translation within the following time limits in accordance with the international application as filed:

​

​

Article 121 

Various kinds of application documents shall be typed or printed, and all the characters shall be in black ink, neat and clear, and free from any alterations. The drawings shall be made in black ink with the aid of drafting instruments, and the lines shall be uniformly thick and well defined, and free from any alterations.

The request, description, claims, drawings and abstract shall be numbered separately in Arabic numerals and arranged in numerical order.