| Document And Entity Information | Sep. 14, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Sep. 14, 2023 |
| Entity Registrant Name | Landos Biopharma, Inc. |
| Entity Central Index Key | 0001785345 |
| Entity Emerging Growth Company | true |
| Securities Act File Number | 001-39971 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 81-5085535 |
| Entity Address, Address Line One | P.O. Box 11239 |
| Entity Address, City or Town | Blacksburg |
| Entity Address, State or Province | VA |
| Entity Address, Postal Zip Code | 24062 |
| City Area Code | 540 |
| Local Phone Number | 218-2232 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Ex Transition Period | false |
| Title of 12(b) Security | Common Stock, par value $0.01 per share |
| Trading Symbol | LABP |
| Security Exchange Name | NASDAQ |
