Computational grids are environment thatprovides the ability to exploit diverse, geographically distributed resources. Bulk Synchronous Parallel (BSP) model is a widely used parallel programming model. With rapid development of grid technologies, users need a new environment that can run parallel programs on computational grids. We present here a new implementation of BSP, which is called BSP-G. It constructs a parallel programming environment on computational grids. In our BSP-G environment, users can make parallel programs with using BSP model and run them on grid. Our BSP-G library uses services provided by the Globus Toolkit for authentication, authorization, resource allocation, executable staging, and I/O, as well as for process creation, monitoring, and control.