Effects of endotoxin-induced lung injury on chemiluminescence(CL) of polymophoneuclear leukocytes (PMNs) are described. In 24 hours after endotoxin injection the peak value of CL of PMNs enhanced markedly though the peak time had no change. Zymosans opsonized by normally pooled plasma and normal self-plasma as well as injuried self-plasma respectively had no effects on CL. The plasma and lung lymph after 2 hours of injury had no activity of promoting CL. These results suggest that a single dose of E. Coli endotoxin should have a strong and lasting effect of activating PMNs and that the Opsonic activity in plasma have no change.