Background The aim of this study was to examine the effect of volunteering for Special Olympics Games (SOG) on the attitudes of volunteers towards inclusion of people with intellectual disabilities. Method A repeated measures design with 3‐week follow‐up was used. There were 100 volunteers recruited for the study and 90 of them completed the study. Results It was revealed that a 1‐week exposure to the SOG improved volunteers’ attitudes towards inclusion of people with intellectual disabilities significantly (P = 0.016). Females had more positive attitudes than males at all three time points of measures. The interaction effect of gender was not significant. Conclusions A 1‐week exposure to the SOG can enhance volunteers’ positive attitudes towards inclusion of people with intellectual disabilities and this effect can maintain for up to a month.