Rhombophryne guentherpetersi is a frog of the family Microhylidae. It is endemic to northern Madagascar and known from the Tsaratanana Massif. It inhabits high-elevation forest and, perhaps, montane grassland, at elevations of 2,000–2,600 m (6,600–8,500 ft) above sea level. It is a rare species that suffers from habitat loss and degradation. It occurs in the Tsaratanana Reserve but the reserve borders are ambiguous, complicating management of the area.