Decker Lake is a lake in the Bulkley River drainage of northwestern British Columbia, Canada.

It lies immediately northwest of the community of Burns Lake.

[1] Its eastern shore is traversed by British Columbia provincial highway 16, where the community of Decker Lake is located.

[2] It is fed by Decker Creek, which enters the lake to the southeast of that community.

[3] The lake was officially given its name in honour of Stephen Decker, who was a foreman with the Collins Overland Telegraph.