OBJECTIVE. To investigate competence of general practice nurses caring for patients with mental health problems in the somatic departments. MATERIAL AND METHODS. A quantitive study on competence of general practice nurses using an anonymous questionnaire was carried out in Klaipeda secondary health care institution in January-February of 2007. The respondents (128 general practice nurses) were selected from seven departments, in which psychiatric consultation was more frequently recommended. In the working places of nurses, 140 questionnaires were distributed; 135 questionnaires were completed (response rate was 96.4%), among them 7 questionnaires were acknowledged as not valid. RESULTS. About 45.0% of general practice nurses had knowledge how to care for the patients with mental health problems, from 1.6 to 21.9% did not have knowledge, and the rest reported having only moderate knowledge (28.1-64.1%). These findings provided a statistically significant link between the duration of employment and education (r from 0.292 to 0.76; P from <0.05 to <0.01). However, only 30.5% of respondents were able to manage conflicts. Most common undesirable events (60.3%) were runaway from inpatient clinic care, injury followed by runaway (29.4%), and suicide (10.3%). From 18.8% to 28.9% of respondents believed that undesirable events were influenced by an unsuitable environment of the department, the shortage of time and personnel, difficulty in getting a psychiatrist's consultation. Only 3.1% of respondents thought that these undesirable events might be affected by the lack of competence of personnel. Most of the nurses (form 75.0% to 84.4%) had a positive attitude toward the patients; however, the nursing principles were recognized only by (6.3% to 24.2%) of respondents. CONCLUSIONS. Competence of the nurses caring for the patients with mental health problems is not at the level required. This may be associated with insufficient professional skills, conflict situations with the patients, and the lack of acknowledgment of the principles of nursing.