An illumination standard calculation method for a tunnel middle section based on safe visual recognition, comprising the following steps: (f) substituting a value of safe stopping sight distance D 0 measured in meter corresponding to the maximum speed limit of the tunnel into the model formula L = 0.683 5.575 − l n D to obtain a value of dynamic minimum brightness value L 0 measured in cd/m 2 required for the tunnel middle section under this tunnel light environment. (g) the tunnel being a simulation tunnel, placing a static test target object B in the tunnel middle section, parking a motor vehicle at a position that is spaced apart from the target object B by a distance Ds, and setting the color temperature of the light environment in the tunnel middle section to be T 0 and the color rendering index of the light environment in the tunnel middle section to be Ra 0 for the tunnel middle section; (h) letting a driver enter the cab of the motor vehicle, adjusting the average brightness L of the light environment in the tunnel middle section from small to large, and recording the static minimum brightness value L f required by the driver to visually discover the static test target object B; (i) resetting at least one of the color temperature and the color rendering index of the tunnel middle section, repeating the step (h) to obtain static minimum brightness values L f associated with a plurality of different sets of color temperatures and color rendering indexes, setting the static minimum brightness value L f0 associated with a color temperature T 0 and a color rendering index Ra 0 as benchmark J, and comparing the benchmark J with static minimum brightness values L f associated with different color temperatures and color rendering indexes to obtain the visual calibration coefficients a associated with different color temperatures and color rendering indexes; (j) calculating the minimum brightness value L 0d of the tunnel middle section under different light environments to be an arithmetic product of a and L 0, which is the safe visual recognition threshold of the tunnel middle section. (f) substituting a value of safe stopping sight distance D 0 measured in meter corresponding to the maximum speed limit of the tunnel into the model formula L = 0.683 5.575 − l n D to obtain a value of dynamic minimum brightness value L 0 measured in cd/m 2 required for the tunnel middle section under this tunnel light environment. (g) the tunnel being a simulation tunnel, placing a static test target object B in the tunnel middle section, parking a motor vehicle at a position that is spaced apart from the target object B by a distance Ds, and setting the color temperature of the light environment in the tunnel middle section to be T 0 and the color rendering index of the light environment in the tunnel middle section to be Ra 0 for the tunnel middle section; (h) letting a driver enter the cab of the motor vehicle, adjusting the average brightness L of the light environment in the tunnel middle section from small to large, and recording the static minimum brightness value L f required by the driver to visually discover the static test target object B; (i) resetting at least one of the color temperature and the color rendering index of the tunnel middle section, repeating the step (h) to obtain static minimum brightness values L f associated with a plurality of different sets of color temperatures and color rendering indexes, setting the static minimum brightness value L f0 associated with a color temperature T 0 and a color rendering index Ra 0 as benchmark J, and comparing the benchmark J with static minimum brightness values L f associated with different color temperatures and color rendering indexes to obtain the visual calibration coefficients a associated with different color temperatures and color rendering indexes; (j) calculating the minimum brightness value L 0d of the tunnel middle section under different light environments to be an arithmetic product of a and L 0, which is the safe visual recognition threshold of the tunnel middle section.