In northern coastal provinces (including Liao Ning, He Bei, Tian Jin and Shan Dong), with the rapid development of industrialization and urbanization, cultivated land protection is in sharper contradiction with economic development in recent years. This paper analyzes the regularity for cultivated land quantity change and its driving mechanism during the last decade in this area by using mathematical statistics. According to component score coefficient matrix of principal components analysis, total component score is worked out. Based on the calculation, the paper builds the linear regressive model of the humanistic driving factors and the cultivated land use change. The study indicates that the three factors, agricultural income and economic growth as well as social development, are the major reasons for arable land change.