According to the demands that calibration organizations need to calibrate various instruments and calibration requirements are complex, a kind of remote calibration system oriented to multiple objects and complex requirements is developed. The system architecture is designed. It’s based on B/S mode, and has the advantage that calibration operation can be done anywhere having Internet access. Then the requirement of remote control is realized. The objects and functions of the system are analyzed in detail, and the object models are built by using object-oriented idea and these models are realized by relation model whose related theories are mature. Then the operation commands can be defined flexibly and the problem that calibration requirements are complex is solved. The theory and experiment shows that the system can be used to calibrate various instruments, its operation command definition is flexible and calibration operation can be done anywhere having Internet access by using the system.