Guided by Social Cognitive Career Theory (SCCT), this study examines how mindfulness among gig workers affects their work satisfaction. It also investigates the mediating role of work–family balance and the moderating influence of the platform work insecurity climate. Using survey data from gig workers in China, the results indicate that gig workers' mindfulness is positively associated with work satisfaction. Additionally, work–family balance mediates the relationship between mindfulness and work satisfaction. The platform work insecurity climate moderates the relationship between gig workers' mindfulness and work–family balance, weakening the positive effect of mindfulness on work–family balance under high platform work insecurity. This study highlights gig workers' mindfulness as a vital personal resource and offers practical suggestions for gig platforms. Specifically, platforms can support gig workers' satisfaction by integrating mindfulness‐related features into their apps and by reducing work insecurity through clearer expectations and more predictable income arrangements.