  The low-luminosity dwarf irregular galaxies are considered. The oxygen
abundances in HII regions of dwarf irregular galaxies were recalculated from
published spectra through the recently suggested P - method. It has been found
that the metallicity of low-luminosity dwarf irregular galaxies, with a few
exceptions, correlates well with galaxy luminosity. The dispersion of oxygen
abundances around the metallicity - luminosity relationship increases with
decreasing of galaxy luminosity, as was found by Richer and McCall (1995). No
relationship between the oxygen abundance and the absolute magnitude in the
blue band for irregular galaxies obtained by Hidalgo-Gamez and Olofsson (1998)
can be explained by the large uncertainties in the oxygen abundances derived
through the Te - method, that in turn can be explained by the large
uncertainties in the measurements of the strengths of the weak oxygen line
[OIII]4363 used in the Te - method.
