The 2017 Ykkönen was the 46th season of Ykkönen, the second highest football league in Finland. The season started on 29 April 2016 and ended on 21 October 2016. The winning team qualified directly for promotion to the 2018 Veikkausliiga, while the second had to play a play-off against the eleventh-placed team from Veikkausliiga to decide who would play in that division. The bottom two teams were relegated to Kakkonen.