The centre-half played 25 top flight appearances for the Saints last season.
Kelly's signing brings to 25 the number of players contracted to Bohs this term
Meanwhile, former Bohs midfielder Robbie McCourt has signed for Waterford.
✍️🏼Bohemians are delighted to confirm the signing of Ciarán Kelly: https://t.co/mYz2ANk47v
— Bohemian FC 🔴⚫ (@bfcdublin) January 16, 2020
Welcome to Dalymount Park, @ciaran_3. pic.twitter.com/6ZaY2nvyAF
