Hosaka (written: 保坂) is a Japanese surname. Notable people with the surname include:
Edward Yataro Hosaka (1907–1961), American botanist
Hideki Hosaka (保坂 秀樹, born 1971), Japanese professional wrestler
Kazunari Hosaka (保坂 一成, born 1983), Japanese footballer
Kazushi Hosaka (保坂 和志, born 1956), Japanese writer
Malia Hosaka (born 1969), American professional wrestler
Nobuto Hosaka (保坂 展人, born 1955), Japanese politician
Nobuyuki Hosaka (born 1970), Japanese footballer
Takeshi Hosaka (保坂 武, born 1945), Japanese politician
Tsukasa Hosaka (保坂 司, born 1937), Japanese footballer and manager
