Background There is growing concern about declining levels of physical activity in childhood cancer survivors. This study aimed to examine the effectiveness of an integrated adventure‐based training and health education program in promoting changes in exercise behavior and enhancing the physical activity levels, self‐efficacy, and quality of life of Hong Kong Chinese childhood cancer survivors. Methods A randomized controlled trial, two‐group pretest and repeated post‐test, between‐subjects design was conducted to 71 childhood cancer survivors (9‐ to 16‐year‐olds). Participants in the experimental group joined a 4‐day integrated adventure‐based training and health education program. Control group participants received the same amount of time and attention as the experimental group but not in such a way as to have any specific effect on the outcome measures. Participants' exercise behavior changes, levels of physical activity, self‐efficacy, and quality of life were assessed at the time of recruitment, 3, 6, and 9 months after starting the intervention. Results Participants in the experimental group reported statistically significant differences in physical activity stages of change (p < 0.001), higher levels of physical activity (p < 0.001) and self‐efficacy (p = 0.04) than those in the control group. Besides, there were statistically significant mean differences (p < 0.001) in physical activity levels (−2.6), self‐efficacy (−2.0), and quality of life (−4.3) of participants in the experimental group from baseline to 9 months after starting the intervention. Conclusions The integrated adventure‐based training and health education program was found to be effective in promoting regular physical activity among childhood cancer survivors. Copyright © 2013 John Wiley & Sons, Ltd.