A series of experiments concerning fusion reactor shielding have been initiated for next fusion devices such as ITER. At the first step the bulk shielding experiments using SS316 materials were performed. Two experimental assemblies were adopted; one was a cylindrical assembly of SS316 (1.2 m in diameter and 1.12 m in thickness) and was set at 0.3 m from the D-T neutron source (Experimental assembly #1), and the other surrounded the D-T neutron source by a source reflector of 0.2 m-thick SS316 adding to the experimental assembly #1 (Experimental assembly #2). Neutron spectra from a few keV to 1 MeV and above 2 MeV were measured at the positions from 0 to 0.91 m in depth using small proton recoil gas proportional counters and a 14 mm-diam. NE213 spectrometer, respectively. Gamma-ray spectra and heating rates were measured using a 40 mm-diam. NE213 spectrometer and TLD, respectively. As neutron spectrum indices, fission and activation reaction rates were measured by fission counters of 235U and 238U, and foils of Al, Ti, Fe, Co, Ni, Zr, Nb, In and Au, respectively. The lower energy neutrons increased more than a few times in the assembly #2 compared with those in the assembly #1 due to neutrons scattered by the source reflector. It is expected that the nuclear data and calculation codes used in nuclear design of fusion devices will be examined based on these experimental data.