Mr Yadav became the first president of Nepal in July 2008, nearly two months after the country's constituent assembly voted to abolish the 239-year-old monarchy.
He is an ethnic Madheshi from Nepal's southern lowlands and was backed by the centrist Nepali Congress - the second largest party in parliament - as well as two smaller parties.
Mr Yadav is a doctor and twice served as health minister.
He has also held senior positions in the Nepali Congress. The presidency is a largely ceremonial position.