The purposes of this research were to study and compare the effects of supplemental complex training on soccer shooting performance. The subjects were 30 soccer players from the College of Physical Education at Bangkok by purposive random sampling and then were randomly sampled into 20 subjects. The subjects were then assigned into 2 groups by random sampling with 10 subjects in each group : the control group had regular training while the experimental group had the supplemental complex training combined with regular training. Both groups trained for 2 days a week for a period of eight weeks. Force and accuracy in soccer shooting performance, and seated leg extension maximum strength of both groups were tested before and after 8 weeks of training. The obtained data were analyzed in term of means and standard deviation while t-test was also employed to determine the significant differences of the data before and after the experiment. After eight weeks of experiment, the results showed that : 1.The average force of shooting by the dominant leg in both groups were not significantly differences at the .05 level between before and after training. However, the average force of shooting by non-dominant leg in the experimental group was significantly higher than the control group at the .05 level. 2. The average accuracy of shooting by dominant and non-dominant leg in both groups were not significant differences before and after training. 3. Seated leg extension maximum strength of both legs in both groups after training were significantly higher than before training at the .05 level. Seated leg extension maximum strength of both legs in the experimental group were significantly higher than the control group after training at the .05 level.
