Abstract: Objective To explore mental health and the effect of mental health intervention among junior middle-school students in Lushan earthquake disaster area.Methods Symptoms Checklist-90(SCL-90), Self-Rating Anxiety Scale(SAS)and Self-Rating Depression Scale(SDS)were used to assess the mental health among 600 students before and after a psychological intervention in the disaster area.Results Before the intervention, the three severe psychological problems in the students were depression(19.83%), anxiety(19.31%), and compulsive symptoms(18.80%).Before the intervention, the female students showed significantly higher scores than the male students in total SCL-90 score(181.42±32.89 vs. 173.61±33.98), somatizatiion(1.61±0.43 vs. 1.54±0.40), depression(2.20±0.49 vs. 2.12±0.53), anxiety(2.14±0.50 vs. 2.03±0.48), terror(2.08±0.54 vs. 1.95±0.53), SDS score(46.97±4.95 vs. 45.81±5.43), and SAS score(43.44±5.75 vs. 42.11±6.86)(all P<0.05).After the intervention, female students still showed higher scores than male students in total SCL-90 score(151.18±30.41 vs. 147.67±24.17), somatization(1.56±0.39 vs. 1.49±0.38), depression(1.72±0.35 vs. 1.65±0.44), anxiety(1.76±0.41 vs. 1.67±0.40), and terror(1.58±0.48 vs. 1.44±0.39)(all P<0.05).After the intervention, both male and female students showed significantly decreased scores in total SCL-90 score and its domains, SDS, and SAS(t=2.190-14.548 for male and t=1.974-14.004 for female;all P<0.05).Conclusion The mental health status was improved obviously after the mental health intervention among junior middle-school students in Lushan earthquake disaster area and there was a gender difference in mental health among the students.