| Document and Entity Information | Sep. 27, 2021 |
| Cover [Abstract] | |
| Entity Registrant Name | S&W Seed Co |
| Security Exchange Name | NASDAQ |
| Amendment Flag | false |
| Entity Central Index Key | 0001477246 |
| Document Type | 8-K |
| Document Period End Date | Sep. 27, 2021 |
| Entity Incorporation State Country Code | NV |
| Entity File Number | 001-34719 |
| Entity Tax Identification Number | 27-1275784 |
| Entity Address, Address Line One | 2101 Ken Pratt Blvd |
| Entity Address, Address Line Two | Suite 201 |
| Entity Address, City or Town | Longmont |
| Entity Address, State or Province | CO |
| Entity Address, Postal Zip Code | 80501 |
| City Area Code | (720) |
| Local Phone Number | 506-9191 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, Par Value $0.001 Per Share |
| Trading Symbol | SANW |
| Entity Emerging Growth Company | false |
