Earthquake is a natural disaster, which causes many psychological problems in survivors. Complicated grief is one of these sequelae. A devastating earthquake with a magnitude of 6.3 on the Richter scale destroyed the city of Bam in Kerman Province, Iran. Twenty-six thousand people were killed. Many of the survivors should have developed psychological problems in the aftermath of the disaster. In this study, we examined the prevalence of complicated grief and its correlation with the demographic factors and some suggested contributing variables. In this cross-sectional study, 400 persons were selected by stratified multistage area sampling. The survivors were interviewed in their temporary residential camp. After evaluating their demographic data, they were evaluated with the inventory of complicated grief. The cut-off point was set to 25. The mean+/-SD age of the participants was 37.8+/-12.7 years. Complicated grief was detected in 304 (76%) of the respondents. Score of complicated grief was higher among women and in those with lower educational levels. Presence in the city during the earthquake, observing burial of corpses, destruction of residential homes during the earthquake, residential problem after the catastrophe, and loss of at least one of the first relatives during previous earthquakes were variables which were correlated with complicated grief. Existence of complicated grief in more than two-thirds of respondents requires more attention of mental health services. Rebuilding of homes and solving the residential problems of survivors are the factors, which could help survivors to find their mental health within a shorter period.