Objectives: The aim of the study is to investigate the effects of eight weeks mini tennis training on coordination skills and reaction time in 8-11-year-old girls. Materials and Methods: The participants of the study were 24 girls aged between 8-11 years. Then were divided into two groups as “experimental” and “control”. The experimental group underwent eight weeks of “Mini Tennis” training. The groups were subjected to the Wall Catch coordination test, and to the visual reaction test via a Newtest 1000 (Finland) device. Tests were applied twice as pre- and post-test. Results for Wall Catch coordination test and Newtest 1000 visual reaction test were compared statistically by Mann-Whitney U and Wilcoxon tests according to Shapiro-Wilks Normality Test’s results and the alpha level was set as 0.05 for statistical significance. Results: Groups’ pre-test and post-test results indicated that there was a significant difference (p=0.002) in favour of the experimental group for post-test, and there was no significant difference (p=0.248) for the control group in the Wall Catch coordination test. There were significant differences (p=0.002 and p=0.003 respectively) in the Newtest 1000 visual reaction test for both groups. In addition; when the two groups’ results were compared; in the pre-test, the difference between groups was not significant (p= 1.000) but in the post-test the difference was significant (p= 0.020) in favour of the experimental group for the Wall Catch coordination test. Conclusion: As a result, it can be claimed that two months of mini-tennis training was effective in improving reaction times and coordination skills of girls aged 8-11 years.