We have reported high Chi(3) values observed for metallo meso-tetra (substituted phenyl) tetrabenzporphyrins (metallo TPTBP). In order to find the relationship between the molecular structures and the Chi(3) values, we have attempted to find relationships between these values and the electronic spectral properties of the compounds. For a series of Zn TPTBPs, we found that the B and Q band peak wavelengths and the peak height ratio between these two bands are related as one would expect from such a series of porphyrins. The Chi(3) values appear to be directly related to the Q/B peak height ratio. For a series of metallo meso-tetra(p-methoxyphenyl) tetrabenzporphyrins, such a correlation of Chi(3) with the spectral properties of various metal species was not apparent. Strategies to increase the Chi(3) values of metallo TPTBP on the basis of these observations are discussed.