The ecological function division is the premise of reconciliation of economy, society and environment 3S technologies are the important guarantee of the accuracy and feasibility for the ecological function division. Taking the city of Puyang in Henan Province as an example, the characteristics and advantages of using 3S technologies for ecological function region division are demonstrated. The 3S technologies can make the data much more accurate, more close to the status quo and more scientific. The spatial analysis function can fulfill the overlay analysis of differently weighed factors. The ecological pattern which deeply influences the ecological function are sufficiently considered in the division process thanks to 3S technologies. All mentioned above greatly improve the reasonability and practical significance of the ecological function division.