  Supernova remnant (SNR) Kes 69 is morphologically characterized by brightened
radio, infrared, and X-ray emission on the southeastern rim, with the 1720 MHz
OH masers detected in the northeastern and southeastern regions at various
local standard rest (LSR) velocities. We have performed a millimeter
observation in CO and HCO+ lines toward \snr. From the northeastern compact
maser region, 12CO and 13CO emission's peaks around 65 km/s and 85 km/s, which
are consistent with the masers' LSR velocities, are detected. In the southeast,
a molecular (12CO) arc is revealed at 77--86 km/s, well coincident with the
partial SNR shell detected in the radio continuum and mid-infrared
observations. An 85 km/s HCO+ emission is found to arise from a radio peak on
the shell. Both the molecular arc and the HCO+ emission at ~85 km/s seem to be
consistent with the presence of extended OH masers along the southeastern
boundary of Kes 69. The morphology correspondence between the CO arc and other
band emission of the Kes 69 shell provides strong evidence for the association
between SNR Kes 69 and the ~85 km/s component of molecular gas. The
multiwavelength emissions along the southeastern shell can be accounted for by
the impact of the SNR shock on a dense, clumpy patch of molecular gas. This
pre-existing gas is likely to be a part of the cooled debris of the material
swept up by the progenitor's stellar wind. The association of SNR Kes 69 with
the molecular cloud at the systemic velocity of ~85 km/s enables us to place
the SNR at a kinematic distance of 5.2 kpc.
