There has been few location-aware system which have two-way system. The playing tag is a very popular game in Japan. This game has a two-way communication in a sense. We have developed an electronic playing tag support system for cooperative game, named EONIGOCO. The system consists of a PDA, a GPS and a mobile phone. We performed five types of experiments at two universities 24 times. Four types are the electronic playing tags and the remainder is a conventional playing tag. The results of experiments were showed below. (1) The devised services based on the electronic playing tag support groupware were better estimation than that of the conventional playing tag. The mutual positioning information using a GPS was effective for the playing tags. (2) If the accuracy of a GPS decrease, we spend a little more time to catch. But the time did not exceed the playing time of the conventional play tag. (3) We can realize the electronic playing tag between remote universities. But we should add the reality using the remainder of five senses for lack of seriousness.