The J. Geils Band /ˌdʒeɪ ˈɡaɪlz/ is an American rock band formed in 1967 in Worcester, Massachusetts, under the leadership of guitarist J. Geils.

The band played R&B-influenced blues rock in the 1970s before moving towards a more new wave sound in the 1980s. Since its initial break-up in 1985, the band has reunited several times.