The aim of this study was to determine whether a set of individual characteristics of children who are engaged in contact sports and children who are engaged in non-contact sports will differentiate these two groups and which of these individual features contribute individually to the distinction. The study involved 154 children (69 children engaged in contact sports and 85 children engaged in non-contact sports). Contact sports involved wrestling, boxing and taekwondo, and non-contact sports swimming, football, athletics and dancing. The measurements used in the research are: Revised Buss-Perry Aggression Questionairre (Buss and Perry, 1992), The Competitive Agressiveness and Anger Scale (Maxwell & Moores, 2007), Revised Sport Motivation Scale (Pelletier et al., 1995), The Sport Anxiety Scale-2 (Smith et al., 2006), Emotion Regulation Questionairre (Gross and John, 2003) and Rosenberg self-esteem scale (Rosenberg, 1989). The results of the t-tests performed for each individual characteristic showed that two groups of children statistically differ significantly in aggressiveness and self-esteem. The group of children engaged in contact sports showed higher levels of aggression and lower levels of self-esteem. The research also investigated aggressiveness in everyday life and aggressiveness specific to sport, competitive aggression (agressiveness during competition or training). The difference between children who are engaged in contact sports and children who are engaged in non-contact sports was also significant in aggression in daily life and in competitive aggressiveness. The group of children involved in contact sports showed higher levels on both aggressiveness scales. Discriminatory analysis has shown that we can distinguish a group of children who are engaged in contact sports from a group of children who are engaged in non-contact sports based on a set of individual characteristics (aggression, intrinsic motivation, self-esteem, anxiety and emotional regulation). Distinction of these two groups was most influenced by aggression in sports, followed by aggression in everyday life and self-esteem. Other features did not prove to be significant for distinguishing these two gropus.