Abstract: A two parameter numerical inverse method of differential equation with only one complementary condition is presented.According to this principle a simultaneous inverse algorithm of lithology parameter and seismic source function of one dimensional wave equation is given in detail.Theoretical analysis and numerical examples demonstrate the existence of solution,stability and accuracy of the method.The method provides a suitable way to solve the difficulty of unknown source function in practical seismic exploration.The numerical results show the feasibility of the algorithm.

Key words: Wave equation, Two-parameter, simultaneous inversion