The effects of quantum deviations from classical behavior of simple fluids are examined using the recently developed perturbation theory of fluids. The free energy is expanded in powers of Planck's constant and in powers of the strength of the attractive potential about an unperturbed system of hard spheres whose diameter is chosen to take into account the softness of the repulsive potential. Using the 6:12 potential, the theory is applied to gaseous helium and hydrogen with good results, and to liquid neon with satisfactory results.