© 2014 Revista Latino-Americana de Enfermagem. Objectives: to analyze the relationship between preoperative emotional state and the prevalence and intensity of postoperative pain and to explore predictors of postoperative pain. Method: observational retrospective study undertaken among 127 adult patients of orthopedic and trauma surgery. Postoperative pain was assessed with the verbal numeric scale and with five variables of emotional state: anxiety, sweating, stress, fear, and crying. The Chi-squared test, Student’s t test or ANOVA and a multivariate logistic regression analysis were used for the statistical analysis. Results: the prevalence of immediate postoperative pain was 28%. Anxiety was the most common emotional factor (72%) and a predictive risk factor for moderate to severe postoperative pain (OR: 4.60, 95% CI 1.38 to 15.3, p<0.05, AUC: 0.72, 95% CI: 0.62 to 0.83). Age exerted a protective effect (OR 0.96, 95% CI: 0.94-0.99, p<0.01). Conclusion: preoperative anxiety and age are predictors of postoperative pain in patients undergoing orthopedic and trauma surgery.