Neutron effects on the mechanical properties and the microstructures of borated stainless steel are studied by irradiating three borated stainless steel batches to different radiation levels (from 1 × 1013 to 1 × 1017 n/cm2). Each batch includes samples varying in boron content from 0.25 to 2.01 wt° and manufactured by two different processes: a powder metallurgical and a conventional wrought technique, which meet the requirements of American Society of Testing and Materials Standard A-887 grades A and B, respectively. A total of 50 tensile specimens, 81 Charpy V-notch samples, and 17 metallographic specimens are used for this purpose. In general, the mechanical properties of samples manufactured by both the powder metallurgy and the wrought techniques show almost no change in mechanical properties with fluence. In addition, no evidence of helium effects are observed during the investigation. Further studies on helium formation in this material during irradiation are ongoing.