In a structurally demanding sports game such as tennis, speed of movement and quick change of direction of movement are one of the most important factors for successful tennis playing at a high competitive level. The main goal of the research was to compare different tests for assessing speed and agility, generic and tennis-specific ones, in order to determine to what extent the results achieved on them can discriminate young tennis players in relation to their competitive performance. A total of 65 young tennis players (38 boys and 27 girls; 10.84 ± 1.67 years old) with at least three years of playing experience who train regularly at least 4 times a week participated in the research. The obtained results showed that to a certain extent the results achieved on agility tests can discriminate young tennis players in relation to their competitive performance. Although the differences between the most successful tennis players who achieve notable competitive results and the less successful players are statistically significant only on the structurally simpler generic (VA"ABCD", LAKUS) and the simplest tennis-specific test (LAKUS - TS), on all the used tests the numerical values of obtained results show that players who belong to a higher competitive performance quality category achieve better results on all agility tests. From the above, it is possible to draw a conclusion that results achieved on agility tests can to a certain extent be used as predictors of competitive performance of young tennis players.