The recoil angle of electron in Compton scattering is incorrect in some text books,and the right sketching of Compton scattering is presented.

• 指出了某些教材中康普顿散射示意图画法的不妥之处；并严格推导了康普顿散射中反冲电子的散射角；给出了正确的康普顿散射示意图.