Herein, preliminary theoretical results for the structural and electronic properties of Hg1−xMnxTe alloys in the zincblende structure using density functional theory calculations are presented. The results suggest that there is a strong dependence of the electronic structure of the alloys on the exchange correlation functional used. When using the generalized gradient approximation, the evaluated data show that this material behaves as a semimetal in almost all Mn concentration range, in disagreement with the experimental data. However, with the hybrid Heyd–Scuseria–Ernzerhof functional calculations, results show that the band gap of these alloys opens for the diluted Mn concentration range 0.05 < x < 0.2, consistent with the experimental observations. Moreover, when considering the magnetic ordering of the Mn spins in the alloy, the results show that, in this material, the lower total spin configurations is energetically more favorable.