Cardioglossa trifasciata occurs in an area that is well surveyed. There is no good quantitative data on its abundance, but it is believed to be declining. The species is threatened by habitat loss caused by agricultural encroachment (including plantations of tree crops), expanding human settlements, and extraction of wood for firewood and building materials. It is not known from any protected area. Suitable habitat might exist on the Rumpi Hills, a site relatively close to Mount Manengouba. However, the area has not been well investigated in recent years, and it is not known whether the species might be found in the Rumpi Hills.