Medvedev was born into a middle-class family in suburban Leningrad (now St. Petersburg (Saint Petersburg)). He attended Leningrad State University (now St. Petersburg State University (Saint Petersburg State University)), receiving a bachelor's degree in 1987 and a law degree in 1990. In 1990 he accepted a faculty position at the university and taught law there until 1999. In 1991 Medvedev joined the legal team of St. Petersburg's newly elected mayor, Anatoly Sobchak, who also had brought future president Vladimir Putin (Putin, Vladimir) into his administration. Medvedev and Putin worked together in the mayor's office for the next five years.

When Sobchak's term ended, Medvedev returned to academic life, and Putin moved to a position at the kremlin. After Putin became acting president of Russia in December 1999, he made Medvedev his protégé. In 2000 Medvedev headed Putin's presidential election campaign, and following Putin's victory he was named first deputy chief of staff. Later that same year, Medvedev was appointed chairman of the state-owned natural-gas monopoly Gazprom. In 2003 he became Putin's chief of staff, and two years later he was appointed to the newly created post of first deputy prime minister.

Throughout his service under Putin, Medvedev distinguished himself as an able administrator with an eye toward reform. His admiration of Western popular culture made some conservatives within the Kremlin uneasy, but much of this criticism was softened after Putin named Medvedev his heir apparent in December 2007. Medvedev responded by stating that Putin would serve as prime minister in his government—leading critics to wonder where executive power would actually reside. The central message of Medvedev's subsequent presidential campaign was “Freedom is better than no freedom,” a remark that hinted at an openness to the West that was uncharacteristic of the Putin years. Medvedev won the March 2008 presidential election by a landslide. Although some outside observers criticized the contest as unfair, most agreed that Medvedev's victory reflected the will of the majority of the Russian people. Medvedev took office on May 7, 2008. Within hours of his inauguration, he nominated Putin to be his prime minister, and Russia's parliament confirmed the appointment the next day.