Analysis is carried for the problem of boundary layer steady flow and heat transfer of a micropolar fluid containing nanoparticles over a vertical cylinder.The goveing partial differential equations of linear momentum,angular momentum,heat transfer and nano concentration are reduced to nonlinear coupled ordinary differential equations by applying the boundary layer approximations and a suitable similarity transformation.These nonlinear coupled ordinary differential equations,subject to the appropriate boundary conditions,are then solved by using the homotopy analysis method.The effects of the physical parameters on the flow,heat transfer and nanoparticle concentration characteristics of the model are presented through graphs and the salient features are discussed.