[Objective] The spatiotemporal variation pattern of land ecological security of Qianjiang District of Chongqing City was studied to provide scientific basis for the sustainable utilization of land resources. [Methods] An evaluation system of land ecological security of Qianjiang District was configured from four aspects of ecological load, ecological protection, ecological function and ecological economy. Methods of subjective and objective combined weight assignment and comprehensive index were used. [Results] Though the land ecological security level of Qianjiang District was not high enough, it was on the rise trend, and there was a big space for it to be improved. The spatial difference of the land ecological security had an obvious pattern with low center and high surrounding areas. [Conclusion] The subjective and objective combined weight assignment overcame the deficiency of single subjective or single objective assignment. The evaluation index system included ecological load, ecological protection, ecological function and ecological economy, and combined with the press-state-response(PSR) model and nature-economy-society model, hence, it could effectively reflect the temporal dynamic change and spatial difference of Qianjiang's land ecological security.