Soil salinization has been a topic due to the widespread recognition of the food crisis and the shortage of cultivated land resources in arid regions. Unfortunately, the evolution of soil salinization under the background of landscape dynamics is rarely addressed due to the lack of spatial coupling techniques. Recent developments in soil science and remote sensing technology provide the possibility for accurate management of land resources. This study aims to explore the spatiotemporal variations of soil salinization by coupling the spatial distribution of soil salinization and landscape patterns in the irrigated northern slopes of Tianshan Mountains. We graded soil salinization levels based on analytic hierarchy process (AHP) method. The results indicated that the proportion of salinized cultivated land in 2014 (32.11%) was higher than that in 2005 (28.11%). We argue that simply quantifying the changes of soil salinization can neither accurately reflect the effectiveness of salinized cultivated land management nor meet the need for land resource planning. In response to these shortcomings, the evolution of soil salinization was explored in three categories, i.e., "stable cultivated land", "increased cultivated land", and "decreased cultivated land". We found that the proportion of soil salinization in stable cultivated land has dropped considerably from 38.11% in 2005 to 29.22% in 2014. This number in the increased cultivated land (59.11%) is much higher than that of the whole study area. These results are expected to benefit local authorities and assist in alleviating the food crisis in arid regions.