Objective To investigate the mental health status among nursing instructors in maternity and child health care hospital, and to explore its relationship with their perceived social support. Methods A total of 288 nursing instructors from a maternity and child health care hospital were selected by cluster sampling, then they were investigated using a general information questionnaire, the Symptom Checklist-90 (SCL-90), and the Social Support Rating Scale (SSRS). Results The total score of SCL-90 among the nursing instructors was 1.61±0.50. Except the score of somatization, other factors score of depression, obsessive-compulsive symptoms, interpersonal sensitivity, anxiety, hostility, terror, paranoia and psychosis were significantly higher than those of the national norm for nurses (P<0.05, P<0.01). The total score of the SSRS among the nursing instructors was 41.50±8.39, and the total score and each dimension score of the SSRS were negatively correlated with the total score and each dimension score of the SCL-90 (P<0.01 for all). Conclusion The mental health and social support level among nursing instructors in maternity and child health care hospital need to be improved. Hospital nursing managers could promote their mental health by enhancing their social support, so as to make the nursing instructors balance work stress and their own needs, and ensure the nursing quality.