The invention discloses a load and environment synchronous coupling simulation testing system and method, and belongs to an environment test chamber and loading device integrated system and method. The load and environment synchronous coupling simulation testing system consists of two parts including a loading device and an environment simulation device, wherein the loading device consists of three parts including a counter-force frame, a hydraulic jack or actuator and a dowel bar; the environment simulation device consists of two parts including a control table and a chamber body; the chamber body internally comprises a temperature system, a salt mist system, a spraying system, an illumination system, a gas injection system, a humidity monitoring system and the like. The load and environment synchronous coupling simulation testing system can achieve the simulation environments of multiple tests including salt mist, salt rain, getting wet in the rain, high-low temperatures, humidity, ultraviolet lamp illumination, acid gases and the like, can develop the structure damage degradation performance test in multiple factors of dry and wet alternation, cycle of freezing and thawing, corrosive gas pickling, corrosive liquid erosion, namely acid erosion, alkaline erosion and salt erosion solutions under a single effect or synchronous coupling effects, realizes synchronous coupling of environment simulation and load simulation, and can truly reflect the actual operation situation of a structure.