| Document and Entity Information | Jan. 03, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jan. 03, 2023 |
| Entity Registrant Name | SEMILEDS CORPORATION |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-34992 |
| Entity Tax Identification Number | 20-2735523 |
| Entity Address, Address Line One | 3F, No.11 Ke Jung Rd., Chu-Nan Site |
| Entity Address, Address Line Two | Hsinchu Science Park, Chu-Nan 350 |
| Entity Address, City or Town | Miao-Li County |
| Entity Address, Country | TW |
| Entity Address, Postal Zip Code | 350 |
| City Area Code | 886 |
| Local Phone Number | 37-586788 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001333822 |
| Title of 12(b) Security | Common Stock, par value $0.0000056 |
| Trading Symbol | LEDS |
| Security Exchange Name | NASDAQ |
