Urban and suburban wildlife have been a problem all over the world. As in Japan, major threats such as deer-vehicle collisions are concerning due to overabundant sika deer (Cervus nippon). Sapporo metropolitan area is the fifth-largest city in Japan with the population over 2.5 million people. The area is surrounded by mountains, forests, and farmlands where urban wildlife is a major threat to citizens. However, preceding studies about urban and suburban deer are very few. The purpose of this study was to observe the seasonal patterns and habitat use of sika deer in Sapporo metropolitan area by spotlight counts and radio-telemetry tracking. We conducted spotlight counts twice a month from 2009 and monitored four deer with VHF or GPS collars. As a result, deer counted by spotlight counts increased each year but decreased in 2013 and then increased again from 2015. Deer were counted the most in April and November, but January to March and June were least counted. Seasonal migration was monitored in all collared deer. Three of the collared deer crossed the railroad to move to their summer home-ranges. Our results suggested that urban deer used farmlands in the summer to gain food and recreational forests in the winter to avoid snow and hunting. In addition, urban deer skillfully utilised small patches of forests and farmlands to move to their seasonal habitats.