[Objective] The status assessment and internal differences of territorial space development and protection in 37 cities in Northeast China were determined in order to identify and discover risks and problems regarding territorial space development and protection in a timely manner in order to provide a theoretical basis for compiling the territorial spatial planning of Northeast China and for exploring the optimization path of territorial spatial development and protection pattern in Northeast China. [Methods] Using a pressure state response (PSR) model, and taking security, innovation, coordination, green, openness, and sharing as the evaluation elements, an evaluation index system of the current situation of land and space development and protection was constructed to comprehensively evaluate the current level of land space development and protection and the interactive relationships of internal factors in 37 prefectures and cities in Northeast China. [Results] ① In 2018, the comprehensive score of the evaluation of the status assessment of territorial space development and protection of 37 cities in Northeast China ranged from 7.35 to 61.41, and the average score was 18.65. ② The average scores of the assessment of the status of territorial space development and protection in Heilongjiang, Liaoning, Inner Mongolia, and Jilin provinces were 20.35, 18.92, 16.77, and 16.34, respectively. ③ The average scores of the pressure layer, the state layer, and the response layer in prefecture-level cities in Northeast China were 5.21, 7.69, and 5.75, respectively. [Conclusion] In 2018, the overall level of territorial space development and protection in 37 cities in Northeast China was not high, and the regional linkage effect was poor. The scores of the pressure layer, the state layer, and the response layer of territorial development and protection in various cities in Northeast China were quite different, and there was no coordinated development of safety, innovation, coordination, green, openness, and sharing.