The nonlinear optical (NLO) properties of different gold metal nanoparticle geometries are reported. The results of nonlinear absorption measurements (as well as optical limiting effects) of both gold nanorods and nanospheres are provided. Gold dendrimer metal nanocomposites were synthesized by first using an amine terminated poly(amidoamine) (PAMAM) dendrimer and later a dansyl chromophore functionalized (PAMAM) dendrimer. The characterization of the nonlinear optical effects in both systems is provided. Another dendrimer morphology containing hydroxy terminated PAMAM G5 was also used as a template to stabilize the gold nanoparticles. These results show that the NLO properties of gold nanoparticles not only depend on the geometry of the metal nanoparticles, but also on the templates used to form the nanocomposites.