Based on density-functional calculations with Hubbard U correction for onsite Coulomb interactions, the structural, electronic, and magnetic properties of V, Mn, and Co-doped FeTe2 monolayers were investigated. Doping is more preferred in Fe-rich conditions than in Te-rich conditions, while Mn inclusion is the most thermodynamically stable in any environment, according to the formation energy. In all doped systems, the energy bandgap was widened, and the electron transport properties were improved. According to our predictions, the V, Mn, Co-doped FeTe2 monolayers are half metal in their ground states with enhanced magnetic moments. These V, Mn, and Co-doped FeTe2 monolayers with interesting electronic and magnetic properties can achieve novel spintronic functionalities.