In the present paper, approximate coordinate transformations for simulation of turbulent flows with wall deformation, significantly reducing computational cost with little degradation in numerical accuracy, are presented. The Wavier-Stokes equations are coordinate-transformed with an approximation of Tailor-series truncation. The performance is evaluated by performing numerical simulations of a channel flow at Re$sub$$ au$/ = 140 with active wall motions of η$sub$m/$^$+/ $leq$5. The approximate transformations provide flow structures as well as turbulence statistics in good agreement with those from a complete transformation [Phys. Fluids 12, 3301 (2000) ] and allow 25-30% savings in the CPU time as compared to the complete one.