The objective of this study was to improve health professionals' knowledge and attitudes toward suicide prevention. A suicide prevention training of 18 hours duration was conducted with 270 health professionals, mainly primary care workers, who were routinely involved with patients at high risk for suicide. Questionnaires were used to assess changes in attitudes and knowledge. The score in the knowledge questionnaire, with 21 points as maximum value, increased from 8.9 to 13 points (p < .001, significance level of 95%). Of the 25 questionnaire items representing attitudes, 18 showed significant change after the training. This training model has enhanced knowledge and attitudes toward suicide prevention in healthcare workers.