In this study we examined the entropy generation in the three-dimensional flow of nanofluid with graphene nanoparticles. Viscous heating function is added in the energy equation to study fluid frictional effects on entropy generation. The modeled equations are converted into ordinary differential equations using appropriate dimensionless quantities. Shooting technique is implemented to acquire numerical solutions. The numerical solutions are also obtained by using Matlab built-in boundary value solver bvp4c for the validation of our numerical code. The obtained results reveal that they are in good correlation. The obtained numerical results are represented by various graphs and illustrated in great detail.