Objective: To assess potential contributors to high injury rates and smoking prevalence among construction workers, we investigated the association of safety climate with personal protective equipment use, and smoking behaviors. Methods: Logistic regression models estimated risk ratios for personal protective equipment use and smoking using data from participants in MassBUILT smoking cessation intervention (n = 1725). Results: Contractor safety climate was negatively associated with the use of dust masks (rate ratio [RR], 0.88; 95% confidence interval [CI], 0.83 to 0.94), respirators (RR, 0.82; 95% CI, 0.75 to 0.89), general equipment (RR, 0.98; 95% CI, 0.95 to 1.00), and fall protection (RR, 0.94; 95% CI, 0.91 to 0.98) and positively associated with current smoking (RR, 1.12; 95% CI, 1.01 to 1.25) but not smoking cessation. Coworker safety climate was negatively associated with the use of dust masks (RR, 0.87; 95% CI, 0.82 to 0.92), respirators (RR, 0.80; 95% CI, 0.74 to 0.87), general equipment (RR, 0.96; 95% CI, 0.94 to 0.98), fall (RR, 0.92; 95% CI, 0.89 to 0.96), and hearing protection (RR, 0.88; 95% CI, 0.83 to 0.93) but not smoking. Conclusions: Worksite safety climate may be important for personal protective equipment use and smoking, but further research is needed.