To realize very high performance computing system, we have proposed a novel opto-electronic 3-D LSI in which both electrical and optical devices are integrated. For realizing such opto-electronic 3-D LSI, through Si photonic via (TSPV) is indispensable for vertical light transmission. In this work, we fabricated the TSPV comprising Si core and epoxy cladding. We measured near field patterns (NFP) of laser light passed through the TSPV to evaluate its light confinement effect. From the results of NFP measurement, we confirmed that the laser light was successfully confined and propagated in the Si core region of the TSPV. We successfully developed a fabrication process to form both the TSPV and TSV simultaneously. The size of the fabricated TSPV and TSV was 20μmx20μm and 16μmx16μm, respectively.