| Cover | 12 Months Ended |
| Dec. 31, 2022 shares | |
| Document Information [Line Items] | |
| Document Type | 20-F/A |
| Amendment Flag | false |
| Document Registration Statement | false |
| Document Annual Report | true |
| Document Transition Report | false |
| Document Shell Company Report | false |
| Document Period End Date | Dec. 31, 2022 |
| Document Fiscal Period Focus | FY |
| Document Fiscal Year Focus | 2022 |
| Current Fiscal Year End Date | --12-31 |
| Entity File Number | 000-53826 |
| Entity Registrant Name | PLASTEC TECHNOLOGIES, LTD. |
| Entity Central Index Key | 0001433309 |
| Entity Incorporation, State or Country Code | E9 |
| Entity Address, Address Line One | c/o Unit 01, 21/F, Aitken Vanson Centre |
| Entity Address, Address Line Two | 61 Hoi Yuen Road, Kwun Tong |
| Entity Address, City or Town | Kowloon |
| Entity Address, Country | HK |
| Title of 12(g) Security | Ordinary Share, par value U.S.$0.001 per share |
| Entity Well-known Seasoned Issuer | No |
| Entity Voluntary Filers | No |
| Entity Current Reporting Status | Yes |
| Entity Interactive Data Current | Yes |
| Entity Filer Category | Non-accelerated Filer |
| Entity Emerging Growth Company | false |
| Document Accounting Standard | U.S. GAAP |
| Entity Shell Company | true |
| Entity Common Stock, Shares Outstanding | 12,938,128 |
| ICFR Auditor Attestation Flag | false |
| Auditor Name | Centurion ZD CPA & Co. |
| Auditor Firm ID | 2769 |
| Auditor Location | Hong Kong, China |
| Business Contact [Member] | |
| Document Information [Line Items] | |
| Entity Address, Address Line One | c/o Unit 01, 21/F, Aitken Vanson Centre |
| Entity Address, Address Line Two | 61 Hoi Yuen Road, Kwun Tong |
| Entity Address, City or Town | Kowloon |
| Entity Address, Country | HK |
| City Area Code | 852 |
| Local Phone Number | 21917155 |
| Contact Personnel Name | Kin Sun Sze-To |
| Contact Personnel Fax Number | 852-27796001 |
