The invention discloses a method for testing the tensile property of a polymer composite strip sample. The method includes the following steps: (i), preparing a strip sample; (ii) measuring the size of the strip sample; (iii) sticking the strip sample; (iv), carrying out an axial tensile test on the strip sample; (v) calculating the tensile breaking strength and axial tensile modulus. The method adopts a tensile test for measuring the tensile property of the strip sample; as the size of the required sample strip is small, the material is reduced; as the load that needs to be added in the test is light, the test operation is relatively simple and convenient. The method provided by the invention not only can test the tensile breaking strength of the strip sample, but also can obtain the axial tensile modulus of the strip sample, and overcomes the defects in the prior art that the whole cylinder is used in the tensile test, and only the axial tensile modulus of the sample is obtained, rather than the tensile breaking strength.