Naomi was born on 16 October 1997. She was born in Osaka, Japan. She was born in the family of Tamaki Osaka and Leonard Francois. She was raised by her parents and her older sister “Mari Osaka.”

Naomi’s sister is also a former professional tennis player. Their parents met when her father was visiting Hokkaido while a college student in New York. Osaka is of Japanese and Haitian Ethnicity. She also has dual citizenship in Japan and America. 

She moved to the United States at the age of 3, completing her basic training. She attended her education at the Elmont Alden Terrace Primary School, and after graduation, she enrolled at Broward Virtual Middle High school. 

Later, she attended the Florida Tennis SBT Academy and the ProWorld Tennis Academy.