Grid computing solves the increasing need of scientific, engineering and research problems. It combines the geographically distributed resources to solve a computation intensive problem which cannot be solved using a single resource. Resource sharing requires more optimized algorithmic structure, otherwise the response time is increased and the resource utilization is reduced. In order to avoid such reduction in the performance of the grid system, an optimal resource sharing algorithm is required. The ACO solves many engineering problems and provides optimal result which includes travelling salesman problem, network routing, and scheduling.