Dissen is located on the southern slope of the Teutoburg Forest at the transition to East Westphalia. The highest point is the Hankenüll (307 meters) on the northeastern city limits. From east to west is the city area about eight kilometers, from north to south about ten kilometers. The land use is composed as follows: 43.8 percent agricultural use, 41.7 percent forest area, 9.8 percent building and courtyard areas and 4.7 percent traffic and other areas.