Abstract: Objective To investigate the death cause of malignant tumors of urban inhabitants in Chongqing and to provide the basis for prevention and control of malignant tumors.Methods Mortality rate,standardized mortality rate,years of potential life lost(YPLL)and YPLL rate were used to analyse death cause of malignant tumors.Results The annual average mortality rate of malignant tumors was 160.99/105 and YPLL rate was 12.78‰.Among malignant tumors,lung cancer took the lead with a mortality rate of 55.49/105,accounted for 34.47%.The next sequences were as follows:hepatitis cancer,oesophagus cancer,stomach cancer and intestine cancer.The sequence of death causes was mostly influenced by sexes,ages and communities.The sequences of YPLL rate of main death causes were:lung cancer,hepatitis cancer,leukemia,stomach cancer and intestine cancer.Conclusion In order to reduce mortality rate of malignant tumors of urban inhabitants,it was important to protect the environment and to change the unhealthy life habits.