Background: Conversion to open surgery of laparoscopic procedures is not in essence a complication, but invalidates the benefits of laparoscopy. Aim: To identify the predictive factors for conversion in laparoscopic colorectal surgery. Material and Methods: Revision of medical records of all patients with colorectal disease operated using a laparoscopic approach, from 1998 to 2010. Gender, age, American Society of Anesthesiologists (ASA) score, body mass index (BMI), previous abdominal surgery, elective/urgency procedure, benign/malignant disease, type of resection and surgeon experience were recorded. A logistic regression model was done to determine which variables were predictive for conversion to open surgery. Results: The medical records of 582 patients aged 57 +/- 17 years (45% men) were analyzed. The rate of conversion to open surgery was 7.1%. The logistic regression model selected as predictors of conversion a BMI over 25 kg/m(2) (odds ratio (OR) 4.9, 95% confidence intervals (CI) 2.4 to 9.9), cancer surgery (OR 2.1, 95% CI 1.1 to 4.3) and male sex (OR 2.30, 95% CI 1.14 to 4.65). The receiver operating curve (ROC) of the model had an are under the curve of 0.766 with 95% Cl of 0.69 to 0.84). Conclusions: A BMI over 25 kg/m(2), male sex and the resection of a malignant tumor were predictive factors for conversion to open surgery.