The low-lying quintet and septet states of MnH have been studied using the state-averaged CASSCF MRCI method. Our study focuses on the A7Π-X7Σ+, c5Σ+-a5Σ+, and b5Π-a5Σ+ band systems, which almost certainly correspond to the 566-, 847-, and 939-nm band systems observed in emission. The radiative lifetimes for the v′ = 0 level of the A7Π, b5Π, and c5Σ+ states are 96.6 ns and 3.2 and 0.39 μs, respectively. Although the CASSCF calculations are not inconsistent with the assignment of the 480-nm band system to a 5Π-a5Σ+ transition, they indicate the existence of a stronger 5Σ+-a5Σ+ transition in the same energy region. The calculations also show that the quintet spectrum above 20 000 cm-1 is very complicated.