The role of Beijerinckia spa and Klebsiella spp in stream litter decomposition was investigated using acetylene reduction method. Beijerinckia and Klebsiella were isolated during the winter and spring of 1980, from the leaves of sugar maple (Acer Saccharum), placed in Bell Creek, Muncie, Indiana. A nitrogen-free media was used to isolate Klebsiella. Both of these organisms were streaked separately on nitrogen-free agar slant tubes, flushed with argon and acetylene added. Gas chromatographic analysis were conducted on the innoculated tubes after incubation for 24 hours at 320 C. Beijerinckia spp, isolated from January, February, and April fixed between 4.48 x 10-7 moles and Klebsiella spp isolated during the same time period was between 1.47 to 8.10 x 10-8 moles. This study indicates that Beijerinckia is a better N2 fixer than Klebsiella in stream litter decomposition.