  We present an analysis of our Chandra Low Energy Transmission Grating
Spectrometer (LETGS) observation of the quasar MR2251-178. The warm absorber of
MR2251-178 is well described by a hydrogen column density, N_H~2x10^21 cm^-2,
and an ionization parameter log(xi)~0.6. We find in the spectrum weak evidence
for narrow absorption lines from Carbon and Nitrogen which indicate that the
ionized material is in outflow. We note changes (in time) of the absorption
structure in the band (0.6-1) keV (around the UTAs plus the OVII and OVIII
K-edges) at different periods of the observation. We measure a (0.1-2) keV flux
of 2.58x10^-11 ergs cm^-2 s^-1. This flux implies that the nuclear source of
MR2251-178 is in a relatively low state. No significant variability is seen in
the light curve. We do not find evidence for an extra cold material in the line
of sight, and set an upper limit of N_H~1.2x10^20 cm^-2. The X-ray spectrum
does not appear to show evidence for dusty material, though an upper limit in
the neutral carbon and oxygen column densities can only be set to N_CI~2x10^19
cm^-2 and N_OI~9x10^19 cm^-2, respectively.
