A floating connector device comprising a fixed housing configured to be fixed to a board, a movable housing movable with respect to said fixed housing, and a contact group with one end configured to be fixed in a row to said board and another end fixed in a row to said movable housing in a longitudinal direction of said movable housing; wherein said fixed housing comprises a long through-hole and a pair of board-facing plates (11b1), positioned at longitudinal ends of said long through-hole, facing said board; said movable housing comprises an outer portion projecting from said long through-hole of said fixed housing and a retaining projection positioned farther on the board side than said board-facing plates (11b1) and overlapping said board-facing plates (11b1) in plan view; said contact group comprises a tail configured to be mounted on said board, a fixing portion supported by a storage fixing groove (11a5) of said fixed housing, an inverted U-shaped portion supported by a contact support groove (12a4) formed in said outer portion of said movable housing, and an elastic deformation portion, connecting said fixing portion and said inverted U-shaped portion, in a free state unsupported by either groove; said elastic deformation portion, by elasticity thereof in said free state, is configured to separate said movable housing from said board, to allow said movable housing to sink in a direction of the board, and in a sunken state, is configured to allow elastic movement in said longitudinal direction of said movable housing, a direction orthogonal to said longitudinal direction, and a tilting direction; stopper projections (12c1) for restricting downward movement of the movable housing are formed on the lower end of the retaining projection, facing the board; and said elastic deformation portion of said contact group comprises an inverted U-shaped portion (13d1), a diagonally downward extension (13d2), a U-shaped fold (13d3), and a diagonally upward extension (13d4) in this order from the fixing portion side that is fixed to said fixed housing. said fixed housing comprises a long through-hole and a pair of board-facing plates (11b1), positioned at longitudinal ends of said long through-hole, facing said board; said movable housing comprises an outer portion projecting from said long through-hole of said fixed housing and a retaining projection positioned farther on the board side than said board-facing plates (11b1) and overlapping said board-facing plates (11b1) in plan view; said contact group comprises a tail configured to be mounted on said board, a fixing portion supported by a storage fixing groove (11a5) of said fixed housing, an inverted U-shaped portion supported by a contact support groove (12a4) formed in said outer portion of said movable housing, and an elastic deformation portion, connecting said fixing portion and said inverted U-shaped portion, in a free state unsupported by either groove; said elastic deformation portion, by elasticity thereof in said free state, is configured to separate said movable housing from said board, to allow said movable housing to sink in a direction of the board, and in a sunken state, is configured to allow elastic movement in said longitudinal direction of said movable housing, a direction orthogonal to said longitudinal direction, and a tilting direction; stopper projections (12c1) for restricting downward movement of the movable housing are formed on the lower end of the retaining projection, facing the board; and said elastic deformation portion of said contact group comprises an inverted U-shaped portion (13d1), a diagonally downward extension (13d2), a U-shaped fold (13d3), and a diagonally upward extension (13d4) in this order from the fixing portion side that is fixed to said fixed housing.