  It is known that the spectral energy distribution (SED) of the nuclear
radiation of narrow-line Seyfert 1 galaxies (NLS1s) has different shapes with
respect to that of ordinary broad-line Seyfert 1 galaxies (BLS1s), particularly
in wavelengths of X-ray. This may cause some differences in the ionization
degree and the temperature of gas in narrow-line regions (NLRs) between NLS1s
and BLS1s. This paper aims to examine whether or not there are such differences
in the physical conditions of NLR gas between them. For this purpose, we have
compiled the emission-line ratios of 36 NLS1s and 83 BLS1s from the literature.
Comparing these two samples, we have found that the line ratios of [O {\sc
i}]$\lambda$6300/[O {\sc iii}]$\lambda$5007 and [O {\sc iii}]$\lambda$4363/[O
{\sc iii}]$\lambda$5007, which represent the ionization degree and the gas
temperature respectively, are statistically indistinguishable between NLS1s and
BLS1s. Based on new photoionization model calculations, we show that these
results are not inconsistent with the difference of the SED between them. The
influence of the difference of SEDs on the highly ionized emission lines is
also briefly discussed.
