A framework based on a three-layer structure for collaborative computing task distribution, deployment and execution over multiple virtual machines has been designed to implement transparent design and placement of tasks. The framework simplifies the interaction among processes with implicit communication,and provides a high reliable and fault-tolerant computing environment. Based on the supporting technologies including virtual appliance technology and application virtualization, six key techniques are proposed for the framework design. They are description of executable files packages and their submission methods, automatic distribution and deployment of executable files, the way of starting and loading tasks, status transition of feature units, message communication language, and system fault tolerance approaches. Based on these key techniques, a prototype system has been developed, and its performance tested. The experimental results show that the framework and key techniques can improve the speed of tasks distribution, deployment and execution, and the system throughput. The task speedup rate is therefore increased.