Osipova, who has been a critic of the Kremlin for many years, said she was not afraid of speaking out.
"What could be worse than what is happening?" said the activist dubbed "the conscience of Saint Petersburg."
"This is my country, my homeland, why can't I speak?"
Osipova first staged a protest in 2002, after Chechen gunmen stormed a Moscow theatre and took 850 people hostage. Since then she has held regular protests and been arrested several times.
Alexander Shishlov of the local branch of the liberal Yabloko party that organised the exhibition said some of the activist's works would violate the current legislation and therefore could not be displayed.
"As long as there are people like Elena Osipova, there is hope," said Sergei, one of the first visitors, who did not give his last name.
The exhibition will run until February 24, the day the Kremlin marks the one-year anniversary of Moscow's offensive in Ukraine.
