| Cover | Nov. 12, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Nov. 12, 2021 |
| Entity File Number | 000-30351 |
| Entity Registrant Name | DEEP DOWN, INC. |
| Entity Central Index Key | 0001110607 |
| Entity Tax Identification Number | 75-2263732 |
| Entity Incorporation, State or Country Code | NV |
| Entity Address, Address Line One | 18511 Beaumont Highway |
| Entity Address, City or Town | Houston |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 77049 |
| City Area Code | (281) |
| Local Phone Number | 517-5000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
