Loneliness, or perceived social isolation, has been positively associated with risk-taking in some categories of risks (e.g. health) but negatively in others (e.g. social). In addition, risk behavior is correlated with risk perception, and loneliness has been associated with changes in perception. This study hypothesized that loneliness would differ in risk-taking behavior across risk domains. Additionally, the study predicted that risk perception would mediate the relationship between loneliness and risk-taking and that resting parasympathetic activity, given its connection to perception, would moderate the relationship. Using the DOSPERT (Domain-Specific Risk-Taking) Scale, the UCLA Loneliness Scale, and HF-HRV (high-frequency heart rate variability), these hypotheses were tested. Results found no evidence of a connection between loneliness and risk-taking, with no moderation or mediation effects. Directions for future studies include further distinctions in loneliness (acute vs. chronic) and risk-taking (active vs. passive).