Drift instabilities in a field reversed configuration are studied under conditions of magneto-inertial fusion (MIF). Specifically, the collisional effect is taken into account because of high-density plasmas in MIF where the drift wave frequency is smaller than the electron-ion collision frequency. Dispersion relations are based on the two fluid equations including the collisional terms; meanwhile, the electromagnetic effect is also considered due to high β values (β is the ratio of plasma pressure to magnetic pressure). It is found that in the limit of low β, the behavior of instabilities described by the dispersion relations in the present paper would become like drift instabilities in tokamaks, where β ∼ 0.1. Therefore, in the MIF case, electromagnetic drift instabilities could be driven by electron-ion collisions due to the charge separation effect. The collisions also bring the phase difference between the perturbed density and the potential perturbation, which is significant for the particle transport.