This study examined the relationship between cardio-kickboxing and balance in individuals with developmental disabilities (DDs). Cardio-kickboxing is a combination of aerobics, boxing, and martial arts. In general, cardio-kickboxing has shown to improve balance in participants. To our knowledge, this is the first adult cardio-kickboxing program for participants with a DD. Twenty-one adults with development disabilities were randomly assigned to either an intervention group or a control group. Participants were tested at baseline, week four, and postintervention using the Four Square Step Test. Improvements were shown in balance (p < 0.0125) at postintervention testing. Results indicate that cardio-kickboxing may be a promising intervention to improve balance for individuals with DDs.