Abstract: A new simplified form of Biot's thermoelasticity solution is presented under steady temperature,and it looks like Papkovich-Neuber's isotropic elasticity solution.Based on thermoelasticity theory,the refined beam theory is derived using Biot's solution and Lur'e method without ad hoc assumptions.For homogeneous boundary conditions,the thermoelastic beam equations consist of three exact equations: the four-order equation,the transcendental equation and the temperature equation.Generalized from isotropic elastic beam problems,thermoelastic beam problems are focused.Approximate beam equations under anti-symmetrical transverse loadings and temperature distribution are derived.