The purpose of this study was to demonstrate a hypothetical approach to evaluate the game sense of rugby football, in which constructing a test to measure such sense in rugby football was a part. Game sense has been defined in the previous study as the ability concerned with the choice of plays in the game. Game sense in rugby football must be considered at two levels, i.e., individual, and unit/team levels. The former is the ability concerned with the choice of individual plays, while the latter being that of unit/team plays as a whole. Every player must have certain game sense at his individual level, but game sense at unit/team level is mainly the concern of the leader. Furthermore, it is conceived that each game situation can be arranged on a continuum by identifying the number of effective plays to choose from for better performance. In this study a ball carrier's game sense at individual level in a situation which has only a few effective plays to choose from was evaluated. For each test item film of actual game situations, depicting various scenes such as scrum or line-out and then leading through to a critical scene was shown. The subject was asked to respond how a ball-carrier should play in each critical situation, and answers were scored. Reliability of the test was estimated by the split-half method and coefficient correlations of .74 was obtained. To examine the validity of the test, two measures were set as criteria, the level of performance in rugby games, and performance in this field experiment, in which the concerned game sense plays a vital part. Both procedures were successful in validating the test. These results suggest that the approach to the evaluation of game sense is promising.