Despite evidence that firearm access in the home is a strong risk factor for firearm injury, firearms are owned more often for self-protection than for any other reason. In this cross-sectional study, we describe the association between firearm ownership and perceived risk of personal firearm injury using logistic regressions applied to data from the 2018 California Safety and Well-being Survey. Most respondents (57.7%) reported being very/somewhat worried about gun violence happening to them. Compared with non-owners in households without firearms, firearm owners were 60% (adjusted OR (aOR) 0.40, 95% CI: 0.27 to 0.58) less likely to be worried about gun violence happening to them; non-owners living in homes with firearms were 46% (aOR 0.54, 95% CI: 0.33 to 0.88) less likely. This suggests an underestimation of actuarial risk that conflicts with the available evidence, with important implications for public health messaging.