In this talk,we introduce two recent results with respect to the integrality and exact solutions of the Fisher type equations and its applications.We obtain the sufficient and necessary conditions of integrable and the general meromorphic solutions of these equations by the complex method.Our results are of the corresponding improvements obtained by many authors.All traveling wave exact solutions of many non-linear partial differential equations are obtained by making use of our results.Our results show that the complex method provides a powerful mathematical tool for solving a large number of nonlinear partial differential equations in mathematical physics.We will propose four analogue problems and expect that the answer is positive,at last.