| Cover | Oct. 27, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Oct. 27, 2021 |
| Entity Registrant Name | OCUGEN, INC. |
| Entity Central Index Key | 0001372299 |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-36751 |
| Entity Tax Identification Number | 04-3522315 |
| Entity Address, Address Line One | 263 Great Valley Parkway |
| Entity Address, City or Town | Malvern |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 19355 |
| City Area Code | 484 |
| Local Phone Number | 328-4701 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.01 par value per share |
| Trading Symbol | OCGN |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
