Vanadium dioxide (VO2) as a thermochromic material has a metal-semiconductor phase transition at the critical temperature of 340 K. The first-principles density functional theory calculations indicate that band gap Eg1 of C, N, F-doped VO2 (M1 phase) at doping atom ratios (1.56%, 3.13%, 4.69%) were reduce to 0.349-0.612 eV, and N-doped M1-VO2 at 4.69% doping atom ratios has a narrowest band gap (0.349 eV). For the systems of C, N, F-doped VO2 (M1 phase), 3.13% N doped VO2 can be used in practice since it can effectively lower the phase transition temperature as well as make little effect on visible light transmittance.