One of the most important skills in softball is throwing. Various methods of training were tested to determine an alternative approach that can improve throwing ball velocity. Combined training is one method that recently gained attention among sports practitioners. However, most training focuses only on the major muscles and neglects supporting muscles such as handgrip and trunk rotation muscles that are also critical in the execution of throwing. Therefore, this study seeks to determine the effect of handgrip, trunk rotation, and combination of handgrip and trunk rotation training on the throwing ball velocity of collegiate female softball players. A total of 72 collegiate female softball players were assigned into 4 strength training groups namely handgrip (HG), trunk rotation (TR), combination (HG&TR) group (CB) and control group (CG). All participants had undergone a training program, 3 days per week for 6 weeks. All groups were instructed to perform the same basic strength training program (training on major muscles) with different additional strength training (handgrip strength or trunk rotation strength) according to the group`s assigned exercises. Participants were assessed on their throwing ball velocity before the intervention (pretest) and after the 6-week training program (posttest). After 6 weeks of training, the result showed that throwing ball velocity significantly increased in the HG (1.45 m/s), TR (1.62 m/s), CB (2.08 m/s) and CG (0.93 m/s) groups. The post-hoc test indicated that all groups were significantly different compared to each other except the comparison between HG and TR groups. This study also demonstrated that the combination training (CB) approach was more effective in improving throwing ball velocity compared to a single mode approach (HG and TR).