We present near-infrared (J, H, and K) photometry and moderate-resolution (
lambda/Delta lambda =3000) K-band spectroscopy of the embedded stellar clus
ter in the giant H II region W31. Four of the brightest five cluster member
s are early O-type stars based on their spectra. We derive a spectrophotome
tric distance for W31 of 3.4 +/-0.3 kpc using these new spectral types and
infrared photometry. The brightest cluster source at K is a red object that
lies in the region of the J-H versus H-K color-color plot inhabited by sta
rs with excess emission in the K band. This point source has an H- plus K-b
and spectrum that shows no photospheric features, which we interpret as bei
ng the result of veiling by local dust emission. Strong Brackett series emi
ssion and permitted Fe II emission are detected in this source; the latter
feature is suggestive of a dense inflow or outflow. The near-infrared posit
ion of this red source is consistent with the position of a 5 GHz thermal r
adio source seen in previous high angular resolution VLA images. We also id
entify several other K-band sources containing excess emission with compact
radio sources. These objects may represent stars in the W31 cluster still
embedded in their birth cocoons.