Abstract: The 650MPa grade hot-rolled steel strip with 4.5mm thickness for automobile rim was produced by using composition design of low carbon, Nb-Ti microalloying and combined with the process of controlled rolling and cooling.The yield strength, tensile strength and elongation of the test steel for the first industrial production in the transverse section are 661, 712 MPa and 25.0%, respectively.The analysis results show that the ferrite grain size in the test steel microstructure is not uniform, and the sizes are 2-10 μm, and the pearlite is ribbon distribution.By lowering the content of Mn, Ti and the finishing temperature, the production process of the experimental steel is improved.The yield strength, tensile strength and elongation of the test steel for the secondary industrial production in the transverse section are 671, 716 MPa and 26.0%, respectively.The ferrite grain is uniform, and the sizes are 2-5 μm.The pearlites are dot-like distribution, and the wheels are passed 1 million times in dynamic radial fatigue test.