Regular participation in resistance training is important for older people to maintain their health and independence, yet participation rates are low. The study aimed to identify motivators and barriers to older people participating in resistance training. A systematic review was conducted including quantitative, qualitative, and mixed-method studies. Searches generated 15,920 citations from six databases, with 14 studies (n = 1,937 participants) included. In total, 92 motivators and 24 barriers were identified. Motivators specific to participating in resistance training included preventing deterioration (disability), reducing risk of falls, building (toning) muscles, feeling more alert, and better concentration. Looking too muscular and thinking participation increased the risk of having a heart attack, stroke, or death, despite the minimal likelihood of these occurring, were barriers. The analysis indicates that increasing participation in resistance training among older people should focus on the specific benefits valued by older people and the dissemination of accurate information to counter misperceptions.