In this paper,the three-dimensional nanofluid bio-convection near a stagnation attachment is studied.With a set of similarity variables,the governing equations embodying the conservation of total mass,momentum,thermal energy,nanoparticles and microorganisms are reduced to a set of fully coupled nonlinear differential equations.The homotopy analysis method(HAM)-finite difference method(FDM)technique is used to obtain exact solutions.The effect of various physical parameters on distribution of the motile microorganisms and the important physical quantities of practical interests are presented and discussed. In this paper, the three-dimensional nanofluid bio-convection near a stagnation attachment is studied.With a set of similarity variables, the governing equations embodying the conservation of total mass, momentum, thermal energy, nanoparticles and microorganisms are reduced to a set of fully coupled nonlinear differential equations. The homotopy analysis method (HAM) -finite difference method (FDM) technique is used to obtain the exact solutions. The effect of various physical parameters on distribution of the motile microorganisms and the important physical quantities of practical interests is presented. and discussed.