| Cover | Nov. 12, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Nov. 12, 2021 |
| Entity File Number | 000-33123 |
| Entity Registrant Name | China Automotive Systems, Inc. |
| Entity Central Index Key | 0001157762 |
| Entity Tax Identification Number | 33-0885775 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | No. 1 Henglong Road, Yu Qiao Development Zone |
| Entity Address, Address Line Two | Shashi District |
| Entity Address, Address Line Three | Jing Zhou City |
| Entity Address, City or Town | Hubei Province |
| Entity Address, Country | CN |
| City Area Code | 86 |
| Local Phone Number | 27-8757 0027 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.0001 par value |
| Trading Symbol | CAAS |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
