Here's the Guide to Deregistration of Motor. Check it out.
Application Form for Motor Vehicle Registration, Transfer, Deregistration/Transfer-in; (with signature of the official vehicle unit attorney or private car owner);
Original copy of Motor Vehicle Registration Certificate;
Original copy of Motor Vehicle Driving Permit;
Motor vehicle license plate;
Where a motor vehicle is discarded as unserviceable or disassembled, the owner should also provide the duplicate copy of the Recycling Certificate of Motor Vehicle Discarded as Unserviceable, owner of vehicle discarded as unserviceable under supervision of the traffic administrative department of the public security organ should also provide the original Motor Vehicle Inspection Records Table;
Where the motor vehicle is lost, the original proof on the loss of the vehicle should also be provided;
Where the motor vehicle is returned due to quality reasons, original proof on the return issued by the motor vehicle manufacturer or the dealer should also be provided;
Where a motor vehicle is not used in China for certain reasons, the owner should also provide copy of exit certificate or the original Notice on PRC Customs-supervised Vehicle Import (Export) License Receiving (Cancellation) issued by customs;
Where the motor vehicle registration is revoked, the owner should provide the Public Security Traffic Management Decision of Revoke and the Recycling Certificate of Motor Vehicle Discarded as Unserviceable issued by the traffic management department of public security organs, duplicate copy;
Where a motor vehicle is illegally assembled or reaches the state standards for discarding motor vehicles as unserviceable, confiscated in accordance with law and compulsorily discarded as unserviceable, the owner should also provide copy of legal instruments of motor vehicle confiscation by law and the duplicate copy of the Recycling Certificate of Motor Vehicle Discarded as Unserviceable;
Application agent should also provide the original copy of identity certificate of the agent and the original copy of the legal written power of attorney provided by the motor vehicle owner.
Processing time limit
Registration should be settled within one working day from the date of acceptance. Suspectable vehicles, materials or certificates will be investigated (The duration of investigation is not included in the time limit).
Motor vehicle discarded as unserviceable
Sell the motor vehicle to Chengdu Xinyuan Renewable Resources Investment Co., Ltd. and apply for deregistration at Xinyuan motor vehicle deregistration service station → obtain a deregistration certificate
Note: Chengdu Xinyuan Renewable Resources Investment Co., Ltd. is the only enterprise in Chengdu that has the qualification for recycling motor vehicles and has been approved by the relevant state department.
Motor vehicle discarded as unserviceable under other circumstances
Submit materials at the service window of the vehicle administration office, branch of traffic police bureau, district (city) county traffic police brigade → obtain a deregistration certificate
The original motor vehicle owner can apply to the vehicle administration office for using the original motor vehicle license plate number when applying for registration of the newly purchased motor vehicle. In such cases, the following conditions should be met: (1) submit application within six months after deregistration; (2) the motor vehicle owner had owned the original motor vehicle for more than three years; (3) illegal act or traffic accident on road traffic safety related to the original motor vehicle has been handled.
Where the original motor vehicle owner needs to keep using the original motor vehicle license plate number, the original owner should confirm that his/her ID number and name have never changed. If there is any change, he/she should get the change of motor vehicle owner information registered before applying for deregistration.
Where the motor vehicle is returned due to quality reasons or not used in China, the owner should get illegal act or traffic accident on road traffic safety related to the motor vehicle handled before application.
In accordance with Document CGF  No. 157 issued by Sichuan Public Security Department: sales of self-disassembled motor vehicle as scrap metal should be applied with written materials provided by the motor vehicle owner including self-disassembly description and contents of voluntarily assuming legal responsibility.
In accordance with Document CGF  No. 157 issued by Sichuan Public Security Department: where a motor vehicle is sold to the discarded vehicle recycling company but hasn’t got deregistered in time, if the prevailing vehicle administration regulations and policies were met when the discarded vehicle was sold, deregistration can be applied with the Recycling Certificate of Motor Vehicle Discarded as Unserviceable and relevant license plate.