Random mechanical properties are experimentally studied on China grade B cast steel wheel. Significant dimples and fabric-like tearing signs were observed firstly and then, lotus flower-like cleavage fracture faces were appeared to indicate the material subjected to a plastic dissipation process under monotonic load. Randomness appears in the deformation process companied with a similarity in total and significant differences in local. Appropriate statistical description is explored with a comprehensive statistical comparison method. Lognormal distribution is excavated out by comparison from seven possible statistical models. Random characters and quantitative measurements have been given for the mechanical properties of China grade B cast steel wheel.