Soil organic matter and total nitrogen are important indexes in evaluating the fertility of black soil. In this paper, based on pedological professional knowledge, soil property data of collected samples were extended to the full space of the study area, and subsequently, the Geographic Information System techniques was applied to explore the dynamic spatial-temporal change of arable soil organic matter and total nitrogen in three periods (1981, 2000 and 2008) of Hainlun City in Heilongjiang Province. Generally, from 1981 to 2008, over 60% of the area of the arable land showed a decrease tendency in organic matter and total nitrogen, which distributed mostly in the middle and southwest regions. The decrease of organic matter mostly happened during the period 1981—2000 with a high decrement (over 15 g/kg). In contrast, during the period 2000—2008, the decrements of organic matter and the area of arable land that organic matter decreased became less, while at the same duration, the decrease of total nitrogen was still severe, in the middle and southwest regions over 70% of the arable land showed a decrease in total nitrogen and among of which 38% decreased over 0.50 g/kg.