Yoga has become increasingly popular in the US and around the world, yet because most yoga research is conducted as clinical trials or experiments, little is known about the characteristics and correlates of people who independently choose to practice yoga. We conducted a systematic review of this issue, identifying 55 studies and categorizing correlates of yoga practice into sociodemographics, psychosocial characteristics, and mental and physical well-being. Yoga use is greatest among women and those with higher socioeconomic status and appears favorably related to psychosocial factors such as coping and mindfulness. Yoga practice often relates to better subjective health and health behaviors but also with more distress and physical impairment. However, evidence is sparse and methodological limitations preclude drawing causal inferences. Nationally representative studies have minimally assessed yoga while studies with strong assessment of yoga practice (e.g., type, dose) are generally conducted with convenience samples. Almost all studies reviewed are cross-sectional and few control for potential confounding variables. We provide recommendations for future research to better understand the correlates of yoga practice.