The invention provides a liquid crystal phased array-based laser radar system, and relates to the technical field of laser phase control. By the liquid crystal phased array-based laser radar system, the problem that incident light and emergent light are separated by a light splitter in an existing light path and the light intensity loss can be caused by introduction of the light splitter so that the application of a beam deflection system is limited are solved. The liquid crystal phased array-based laser radar system comprises a central processing unit, a laser emission system and an echo receiving system, wherein the laser emission system comprises a laser A and an emission light path, the emission light path comprises a beam expansion collimation system A, a refined deflection system, aone fourth wave plate and a rough deflection system, the refined deflection system comprises a one second wave plate, a liquid crystal spatial light modulator (LCSLM) and a DSP controller, the rough deflection system comprises a liquid crystal polarization rotator, a liquid crystal spatial light modulator (LCPG) and a polarization grating controller, and the echo receiving system comprises a fieldprogrammable gate array (FPGA), an MPPC and a receiving light path. An oblique incidence mode is employed, an included angle between light irradiating the liquid crystal spatial light modulator and emergent light is increased, the light path is simplified, the system volume is reduced, the light intensity loss caused by the light splitter is also reduced, and the application range of the liquid crystal spatial light modulator is expanded.