To provide a floor hinge capable of preventing outflow of oil from a floor hinge body over a long period of time.

The floor hinge includes: a rod 2 provided, on the upper end, with a connection part 2b for connection with the lower part of a door 15; the floor hinge body 3 which has a swollen part 3b raised and swollen in a disk shape around a support hole 3c made to pass through the upper end side of the rod 2 and projected so as to be freely rotated, and energizes the lower end side of the rod 2 in the inside so as to rotate the door 15 connected to the connection part 2b in a closing direction; a sealing material 6 which seals a gap of the rod 2 and the inner wall surface of the support hole 3c and prevents the outflow of oil stored inside the floor hinge body 3; and a metallic dust-proof cap 4 disposed at the upper part of the swollen part 3b with an external fitting hole 4a, which has a diameter smaller than that of the rod 2 and can be externally fitted to the rod 2, fitted to the rod 2 projecting from the support hole 3c.