We report plasmon excitation in 3-dimensional, ordered, gold nanocrystal(NC) arrays using a prism coupler. The gold NCs are arranged in the silica host matrix in a face-centered cubic lattice with the mono-dispersion gold core size of ∼3 nm. We observed the collective optical behavior of the gold NC array and found a blue shift in the plasmon absorption peak with increasing gold volume fraction (Au loading). Plasmon resonance bands centered at 536, 530 and 520 nm are measured for gold NC arrays with gold loading factors of 0.25, 0.5 and 1.0, respectively. The corresponding angular spectra of the gold NC arrays show resonance angles at 60.3, 63.3 and 66.4 degree.