Hiromi "Kumi" Isozaki (Japanese: ?? ??; born 20 March 1965) is a Japanese former track and field athlete who competed in sprinting events from 100 metres to 400 metres.
She won four gold medals at the 1982 Asian Games, which she set three games records.
She later won 400 m bronze at the 1986 Asian Games and a 200 metres bronze at the 1987 Asian Athletics Championships.
She was also a three-time silver medallist in the 4×400 metres relay at continental level.
She was a ten-time winner at the Japan Championships in Athletics, seven of those coming in the 200 m.
She was a Japanese record holder in the 200 m and 400 m with her bests of 24.00 seconds and 53.73 seconds, titles she held for nearly ten years.
She was also a former Asian record holder in the 4×100 metres relay and 4×200 metres relay with the Japanese national team.