The influence of the different phase functions on the spatially resolved reflectance measurements is studied with Monte Carlo simulations. We show that the spatially resolved reflectance from a homogenous semi-infinite medium is mostly dependent on the second-order factor of tissue except for the absorption coefficient, the reduced scattering coefficient and the refractive index at short source-detector separations. However, the effect of the high-order-factors is very weaker. Then we analyze the given conclusion and find that the parameter varies with the same current following the first-order moment for the phase functions containing two parameters.