The electrical properties and the Hall effect in semiconductor compounds Ag0.01Mn0.99S and Tm0.01Mn0.99S have been studied in the temperature range 80–400 K in a magnetic field of 12 kOe. The mechanism of conduction is established, which depends on the type of doping and concentration from the current - voltage characteristics. At the replacement of manganese by silver, the Mott type was found, and the replacement by thulium causes ohmic conductivity. The mobility and type of charge carriers are found from the Hall constant.