The festival was the final event of the extensive programme entitled the Russian Language and Modern Russia, which was designed to draw public attention to the modern Russian language and purify it.
Mrs Putin arrived at the closing ceremony, which took place at St Petersburg State University.
"We have gathered here as we love the Russian language. The Russian language unites all people who care about Russian culture. Preserving linguistic knowledge and using it must be every Russian's duty," said Mrs Putin.
It is culture, rather than business interests, that attracts people from across the world to Russia, emphasised Mrs Putin.
The first lady thanked international organisations, i.e. the Association of Russian Language and Literature Teachers, the Russian Society and others, for the propaganda of Russian abroad.
Mrs Putin expressed hope that such festivals would be held in Russia on a regular basis.
Philologists from Russia's leading universities, writers and journalists were engaged in the Russian Language and Modern Russian programme. They studied a few thousand questionnaires from across Russia. The results of their monitoring were summed up in a booklet, which will be distributed among universities, newspapers and government bodies.
The festival programme included contests for the best command of Russian among journalists, writers, politicians, school and university students. Winners received awards at today's ceremony.