We have obtained HST-NICMOS observations of five of M31's most metal-rich globular clusters: G1, G170, G174, G177 & G280. For the two clusters farthest from the nucleus, G1 and G280, we statistically subtract the field population and estimate metallicities using K-(J-K) color-magnitude diagrams (CMDs). Based on the slopes of their infrared giant branches we estimate [Fe/H] =-1.22±0.43 dex for G1 and -0.15±0.37 dex for G280. We combine our infrared observations of G1 with two epochs of optical HST-WFPC2 V-band data and identify at least one LPV based on color and variability. The location of G1's giant branch in the K, (V-K) CMD is very similar to that of M107, indicating a somewhat higher metallicity than our purely infrared CMD; [Fe/H]= -0.9±0.2 dex.