The field monitoring test on loading and response of lining structure of a rectangular shield tunnel is carried out; the main loading stages, external load and response of lining structure are discussed, so as to learn the mechanical behavior of lining structure of rectangular shield tunnel during construction. The test results show that: 1) The loading of lining structure during construction can be divided into 4 stages, i.e. dead weight stage, shield tail passed stage, synchronous grouting stage and load stabilizing stage. 2) The load of lining structure in shield tail passed stage and synchronous grouting stage are 1.5-3.0 and 1.5-2.5 time that in load stabilizing stage respectively. 3) The external load and its distribution rules of lining structure in load stabilizing stage coincide with theoretical calculation results. 4)The internal force of lining structure during construction is bilaterally symmetry; and the distribution characteristics of internal force during construction coincide with those during operation.