  The relativistic energy-band calculations have been carried out for
UFeGa_{5}, UCoGa_{5} and URhGa_{5} under the assumption that 5f-electrons are
itinerant. A hybridization between the U 5f state and Ga 4p state occurs in the
vicinity of the Fermi level. The Fermi surface of UCoGa_{5} is quite similar to
that of URhGa_{5}, which are all small in size and closed in topology.
UFeGa_{5} has the quasi-two-dimensional Fermi surface which looks like a
lattice structure.
