A convenient and efficient synthesis of B-10 enriched sodium borohydride [Na10BH4] from commercially available 1 B-enriched boric acid [B-10(OH)(3)] is described. The reaction sequence B-10(OH)(3) -> B-10(On-Bu)(3) -> (BH3)-B-10.Et3N -> (NaBH4)-B-10, afforded the product in 60-80% yield. The reaction was successfully scaled to hundreds of gram per run.