The squeezing properties of light field interacting with the A-type three level atom via intensity-dependent coupling are studied and the influences of detuning between the atomic transition frequency and the light frequency in single-photon process and the initial squeezing of light on the light squeezing are discussed emphatically. The results show that both the detuning and the initial squeezing of light strongly influence the squeezing of field. The light squeezing remains continuous if the detuning is big enough, but if the detuning is little the light field will be squeezed periodically. The bigger the initial squeezing factor of light is, the deeper the light squeezing is.