The 2017 season was the Seattle Seahawks' 42nd in the National Football League (NFL) and their eighth under head coach Pete Carroll. The Seahawks tried to improve their 10–5–1 record from 2016. However, it did not happen because of injuries to key defensive players and poor offensive performances. After the Atlanta Falcons' Week 17 win over the Carolina Panthers, they were eliminated from playoff contention for the first time since 2011. They also failed to achieve a 10-win season for the first time since that same season. This was Russell Wilson's first season not making the playoffs.

During the season, Russell Wilson broke Eli Manning's NFL record for most 4th quarter touchdowns in a single season with 18; the previous record was 15. Wilson also led the NFL in touchdown passes with 34.

This was also the final season of the original Legion of Boom playing together, as well as the 21st and last full season under the ownership of Paul Allen, who died during the 2018 season.

Draft trades

All undrafted free agents were signed after the 2017 NFL draft concluded on April 29, unless noted otherwise.

Divisional matchups: the NFC West played the NFC East and the AFC South.

Note: Intra-division opponents are in bold text.

at Lambeau Field, Green Bay, Wisconsin