The invention relates to an environmental simulation calibration wind tunnel of an annular loop. The environmental simulation calibration wind tunnel of the annular loop is formed by a connection section, a power section, a refrigeration section, a heating section, a vacuum control section, a large cornering section, a rectification section, a contraction section, a replaceable test section, a diffusion section and a small cornering section which are sequentially connected. A draught fan is arranged or connected inside the power section, an evaporator or a heater is arranged inside the refrigeration section or the heating section, and a vacuum control system is arranged outside the vacuum control section. The outer wall of the contraction section is connected between the rectification section and the replaceable test section, the contraction ratio of the rectification section to the replaceable test section is 5-8 to 1, and the external diameters of the replaceable test section are the same in the length direction. The external diameter of the end, close to the replaceable test section, of the diffusion section is smaller than the external diameter of the end, close to the small cornering section, of the diffusion section. The environmental simulation calibration wind tunnel of the annular loop can be calibrated under the condition that the operating temperature, pressure and wind speed of an atmosphere device are simulated and detected.