Periodic blazed grating of binary grating limits the number and distribution of the diffraction angles realized by liquid crystal phased array (LCPA). Inspired by microwave radar phase arrays theory, a beam steering approach of liquid crystal phased array based on a nonperiodic blazed grating is proposed. Through the deduction of diffraction theory, it is verified that periodic blazed grating is a special case of nonperiodic blazed grating. Simulations are presented to testify that the beam steering approach based on nonperiodic blazed grating can obtain steering angles which are ten times as many as those produced by periodic blazed grating. Without combining with other devices, LCPA can realize continuous beam steering of almost all the resolvable spots over the field of view and will not decrease diffraction efficiency. In order to validate the proposed approach, beam steering experiment is performed with single LCPA. The results show that the beam steering approach based on nonperiodic blazed grating can obtain continous beam steering and steering angles which periodic blazed grating cannot.