In order to study the mechanical properties and deformation characteristics of cement stabilized aggregates mixed with modified waste plastic fiber materials, relying on the Huaizhi Expressway project, a test road was paved to verify the feasibility of waste plastic fibers applied to cement stabilized aggregates base layer, and to put forward the mixing process of cement stabilized aggregates mixed with waste plastic fibers. The test results show that the splitting tensile strength and bending tensile strength of cement stabilized aggregates can be significantly improved by mixing appropriate amount of modified waste plastic fibers. The split tensile strength of cement stabilized aggregates at the age of 7 d increased by 71.4% and the flexural tensile strength increased by 13.1% when 0.30% of modified waste plastic fibers were added. Adding 0.30% of modified waste plastic fiber can effectively reduce the dry shrinkage deformation coefficient and temperature shrinkage deformation coefficient of cement stabilized aggregates. The investigation of the paved test road showed that the core samples were qualified in terms of unconfined compressive strength, and the crack-resistant performance of the cement-stabilized crushed stone base layer with waste plastic fibers was significantly improved.