Background: Symmetry of movement actions in sport is considered as an element of versatility which enlarges an individual’s technical and tactical capacity. Asymmetry usually limits this capacity and may also lead to overstrains of one side of the body and cause an injury. The research is done on health aspects and practical improvement in sport contest. Up-to-date research on judo contest effectiveness has been aimed at the ability of throwing into various directions. There is no material and data as compared to the directions of throwing and effective directions of the opponent’s attack. The purpose of this research was to find relationships between the directions of the executed throws and the side of competitors’ bodies used while throwing. Material/Methods: Within 2005-2010 1,968 judo contests were recorded by means of a graphic method of recording of a judo contest during 587 domestic and international judo competitions. 12 competitors (6 men and 6 women) were subject to our observations. The effectiveness of throws performed into 4 directions and of the used body side was determined on the grounds of the average number of points won or lost during a contest. Results: The effectiveness of judo throws performed to the left direction or by using the left side of the body is similar or higher to those performed to the other side. There is a relationship between the dominant part of the body while throwing and the directions of throwing, and the defense efficiency in relation to the directions and ways of executing throws by opponents. Conclusions: The effectiveness of the left attack directions and using the left side of the body may result from the training practice. It seems rational to find reasons for such high effectiveness of the left attack directions and the dominance of the side of the body while throwing.