Two-photon absorption induced polymerization provides a powerful method for the fabrication of intricate three-dimensional microstructures. Recently, Lucirin TPO-L was shown to be a photoinitiator with several advantageous properties for two-photon induced polymerization. Here we measure the two-photon absorption cross-section spectrum of Lucirin TPO-L, which presents a maximum of 1.2 GM at 610 nm. Moreover, from the two-photon absorption spectrum we determined that Lucirin TPO-L radical quantum yield is independent of the wavelength. Despite its small two-photon absorption cross- section, it is possible to fabricated excellent microstructures by two-photon polymerization microfabrication due to the high polymerization quantum yield (0.99) of Lucirin TPO-L. These results show that optimization of the two-photon absorption cross-section is not the only factor to be considered when searching for new photoinitiators for microfabrication via two-photon absorption.