| Cover | Dec. 14, 2021 |
| Cover [Abstract] | |
| Entity Registrant Name | GEE GROUP INC. |
| Entity Central Index Key | 0000040570 |
| Document Type | 8-K |
| Amendment Flag | false |
| Entity Emerging Growth Company | false |
| Document Period End Date | Dec. 14, 2021 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Incorporation State Country Code | IL |
| Entity File Number | 1-05707 |
| Entity Tax Identification Number | 36-6097429 |
| Entity Address Address Line 1 | 7751 Belfort Parkway |
| Entity Address Address Line 2 | Suite 150 |
| Entity Address City Or Town | Jacksonville |
| Entity Address State Or Province | FL |
| Entity Address Postal Zip Code | 32256 |
| City Area Code | 630 |
| Local Phone Number | 954-0400 |
| Security 12b Title | Common Stock, no par value |
| Trading Symbol | JOB |
| Security Exchange Name | NYSE |
