An outstanding representative of the Gunzburg family, David Gunzburg left a mark not only on the history of the St. Petersburg Jewish community but on the history of Russian science as well. He received a brilliant home education, and attended lectures by leading orientalists in St. Petersburg and Paris. In 1877 he was awarded an academic degree at St. Petersburg University. He also studied Arab poetry and paid much attention to Jewish history. He accumulated a rich library and collection of Jewish manuscripts. In cooperation with Stasov, Gunzburg published a book entitled "The Jewish ornament" in Berlin. One of his major works was the catalogue of manuscripts kept in the Oriental Languages Department of the Ministry of Foreign Affairs. In his last years David Gunzburg worked on the editorial board of the "Jewish Encyclopedia".
David Gunzburg was closely acquainted with a well-known archeologist and numismatist, liberal minister Count I. Tolstoy who held the office of Minister of Education from October 1905 until April 1906. In 1907 Tolstoy, David Gunzburg, Milyutin, a leader of the "Union of 17th October" party, Ukhtomsky, editor of the newspaper "Peterburgskiye Vedomosti", philosopher Radlov and chief procurator of the Synod Izvolsky united into the "Society for Equality and Fraternity". Regardless of their political views, the members of this Society undertook to restore "peace, truth and justice" everywhere, to "bring its spirit to the University, to the State Council and State Duma and also, through teachers, to the secondary and elementary schools". The goal of the society was to achieve equality for all nationalities in Russia.
David Gunzburg followed in his father's footsteps, retaining all his positions in the Jewish community and charities. He provided support for Jewish educational and charitable institutions not only in St. Petersburg but throughout Russia, including the Pale. In St. Petersburg, the talmud-torah "Mogen David" was opened at his expense. He made generous donations for studies in Jewish history. David Gunzburg was the founder of the Society for Oriental Studies, and Society for Relief for Poor Jews of St. Petersburg, a member of committees of the Society for the Spread of Education among Jews of Russia (OPE) and Society for Handicrafts and Agricultural Work among Jews (ORT), as well as the Central Committee of the Jewish Colonization Society (JCS).
As head of the St. Petersburg Jewish community, David Gunzburg followed his father in preserving traditions and rejecting radical reforms. He made every effort to achieve the emancipation of Jews, but, like his father, he thought it could be done by petitioning the government with the support of high level liberal government officials. In his opinion, even a gradual relaxation of laws in respect to Jews, would be a step towards emancipation. In the early 20th century such a position could not satisfy a large part of the Jewish Community. By nature, David Gunzburg was a scholar, educator and philanthropist, rather than a political leader or businessman. Everyone who knew him noted his gentleness, delicacy and responsiveness. David Gunzburg died in 1910, the only member of his family to be buried in St. Petersburg.