We present new constraints on the two Higgs doublet model (THDM) and the leptoquark model parameters using the leptonic and semileptonic decays of the D meson. Our global analysis includes: the leptonic decay of the Ds meson, the semileptonic decays of the D0 and mesons and we have included the spectral distribution of the and measured by CLEO. We show that D meson decays effectively constrain several variations of the THDM, namely: Type I, Type II, Lepton Specific (LS), Flipped and the aligned model with a Z2 symmetry while complementing second generation constraints for leptoquark models.