The purpose of the present study was to record the incidence of knee injuries in Greek artistic gymnasts in relation to the event and exercise phase. Two hundred artistic gymnasts aged 12.2 + 2.8 years from different clubs of North and South Greece volunteered to participate in this study for the 2010-2012 seasons. Authors twice a week registered any injury occurred during practice or event which made the gymnast miss the next practice or event session. Results showed that gymnasts sustained 49.5% of knee injuries in landing mainly in the floor routines causing ligament sprains with these injuries to be occurring at the pre-competition season, usually during training time. Furthermore, knee injuries at take off phase (11.9%) occurred mainly in the vaulting horse on forward rotation exercises on the first competition level. Conclusively, coaches mainly must use supplementary soft mats during training to restrict pressure on knee joints on landing phase and control the amount of jumping in an effort to reduce the possibilities to increase knee injuries, especially in this particular age group gymnasts.