We have been developing Hybrid OpenCL, which enables the utilization of OpenCL devices by connecting them over the network. Hybrid OpenCL opens a gate to scale up OpenCL environments. By using Hybrid OpenCL, applications written in OpenCL can be easily ported to high performance cluster computers, thus, Hybrid OpenCL can provide more various distributed and parallel computing platforms. Hybrid OpenCL consists of two elements, a runtime system that provides the abstraction of OpenCL implementations and a bridge program that connects multiple OpenCL runtime systems over the network. This paper describes the design and implementation Hybrid OpenCL. Its performance for distributed processing is evaluated by using multiple nodes. The experimentation results show that the overhead introduced by Hybrid OpenCL is minimum and comparable with the combination of MPI and OpenCL.