If you had Russian ancestors of Jewish religion living in St Petersburg before the Revolution you are in luck.
The St Petersburg historical archive digitised the metrical records ( birth, death and marriage) and uploaded them on their website. They are not indexed. Manual page by page research within the book is required.
Fund 422 inventory 3 has the collection of metrical records for Choral Synagogue in St Petersburg. The collection also has the books for those buried at Volkovskoe cemetery for the period 1820-1871 (fund 422, inventory 1 , files 158-159) and the books for buried at Preobrazhenskoe cemetery for the period 1875-1918 (files 162-244).
Preobrazhenskoye (Transfiguration) Jewish Cemetery was created in 1875. It started as a separate burial place for adherents on non-Christian religions. On the territory of the cemetery, one can see impressive tombs (many of them designed by famous architects) of prominent representatives of the St. Petersburg Jewish community.
In addition, you will find lists of employees of Jewish Community (1892-1894, 1918) and teachers of Jewish secondary schools (1893-1906), lists of employees of the Synagogue (1894-1906, 1919-1921), lists of boys singers (1905-1906) and many more various records.
Fund 1129 has the collection of metrical books for Kronstadt synagogue (1875-1909).
If you are looking for post -Revolutionary metrical records than look no further than ZAGS archives in St Petersburg.
Do not forget the online project – Jewish cemeteries in St Petersburg database.
Remember that the information you are looking for may fall within the scope of the law on Archival Affairs in the Russian Federation. Under this law there might be a restricted access to archival documents. Since it will contain information about the personal and family ”secrets” of a citizen. A 75-year term from the date of creation of the specified document applies. Let’s say the document is created less than 75 years ago. Then you need to provide the archive with documents, confirming your kinship with your ancestor.