The optical properties of hexagonal nanohole arrays in gold films are investigated. Nanosphere lithography combined with reactive ion etching has been applied as a low cost method to fabricate nanohole arrays with hexagonal symmetry where the size and spacing of the holes can be independently controlled. In this study, the spacing between the nanoholes is 600 nm with the hole diameter varied between 450 and 250 nm. The transmission spectra of the surface patterns with different film thickness are collected with normally incident light. The color of the reflected light from the nanohole array was found to change from green to red as the diameter of the holes was reduced. One application of these films is to study cell adhesion to small areas with controlled size. We explore the possibility of making isolated cell adhesion dots by chemically modifying the nanohole area. Swiss 3T3 cells were adhered onto the patterned surface and imaged using environmental SEM and fluorescent microscopy.