According to energy conservation and finite difference method, strip transient temperature model was established with high operation speed and good operation precision, which used discretization mesh in strip cross section, analyzed energy conversion of each control volume, transformed differential equation into difference equation, built various node difference equations, used two dimension alternating difference for equations solution. Based on the transient temperature field model, influence rule of strip transverse temperature was analyzed with different strip thickness, width and slab initial temperature difference. The research results show that strip transverse temperature in finishing stand is direct proportion to strip thickness, width and slab initial temperature difference. The results also provide theoretical support for the transverse temperature difference improvement in hot rolling.