Lenvik () is a former municipality that was located in the old Troms county, Norway. The municipality existed from 1838 until its dissolution in 2020. The municipality was partly situated on the mainland and partly on the island of Senja in what is now Senja Municipality in Troms og Finnmark county. The administrative centre was the town of Finnsnes, where the Gisund Bridge connects Senja to the mainland on Norwegian County Road 86. Other villages in the municipality included Aglapsvik, Gibostad, Botnhamn, Fjordgård, Finnfjordbotn, Husøy, Langnes, Laukhella, Silsand, and Rossfjordstraumen. The lake Lysvatnet was located in the municipality on Senja island, west of Gibostad.