Raina was born in the western Indian state of Gujarat to a Kashmiri Pandit family. Her middle-class Hindu family hails from the town of Tral in Pulwama district, Kashmir. Her family left Kashmir in the early 1990s during the exodus of Kashmiri Hindus, due to the ongoing insurgency in Jammu and Kashmir. Raina is fluent in Hindi, Gujarati, and English. Raina briefly studied at Brihan Maharashtra.
At the national events, Raina has represented her home state Gujarat. Her idols growing up were Roger Federer, Rafael Nadal, Serena Williams and Sania Mirza.
Raina trains at the Hemant Bendrey Tennis Academy at the PYC Hindu Gymkhana in Pune. Previously coached by Hemant Bendrey, she is now coached by Arjun Kadhe, who is also her trainer and hitting partner.