  We observed a group of galaxies, HCG 57, with ASCA. Regardless that their
member galaxies are dominated by spiral galaxies, we detected extended thermal
X-ray emission that is attributed to hot gas with a temperature of
$1.04\pm0.10$ keV. This is the second clear detection of thermal X-ray emission
from a spiral-dominant group of galaxies after HCG 92. The luminosity of the
thermal emission is about $5\times10^{41}$ erg s$^{-1}$ in the 0.5--10 keV
band, which is higher than that of HCG 92, but relatively less luminous among
groups of galaxies. The X-ray emission is extended over several member
galaxies, and is thus associated with the group rather than an individual
galaxy. The metal abundance cannot be well constrained with a lower limit of
0.08 solar. The gas-to-stellar mass ratio is $\sim0.3$. Although this is
relatively low among groups, the hot gas is also a significant component even
in the spiral-dominant group. We suggest that the X-ray faintness of
spiral-dominant groups is due to the low surface brightness and somewhat low
gas mass, at least in the case of HCG 57.
