In order to improve the fault isolation and restoration test on distribution automation systems（DAS），a host and terminal coordinated injection test approach is put forward.The starting condition of DAS is injected by the host injection equipment.The fault information of the other terminals on the feeder are injected by the terminal injection equipment.The simulated switches made up of relays are implanted to replace the feeder switches.Thus，the fault isolation and restoration property of DAS can be tested without outage.By implanting a few terminal injection installations on the corresponding feeder terminal units in turn while the fault information of the other terminal units is injected by the host injection equipment，the amount of terminal injection equipment and the manpower can be reduced.Comparisons are made between the host injection test approach，the terminal injection test approach and the proposed coordinated approach of host and terminal injection.An example is given to show the feasibility and advantages of the test approach proposed.