Topical application bioassays of bifenthrin and lamba-cyhalothrin were conducted using 7 field collected populations of annual bluegrass weevils, Listronotus maculicollis (Dietz). The populations were located on golf courses in Connecticut. Two populations from golf courses with historically low pyrethroid input (low-usage) were compared to five populations from golf courses with historically high pyrethroid input (high-usage). The LD50 for each insecticide and each population was estimated by concentration-mortality regression lines. The estimated LD50‘s were then used to calculate resistance ratios for comparisons relative to the most susceptible population for each insecticide. This study demonstrates the development of moderate to high levels of resistance to this class of insecticide on high-usage golf courses in southern New England. This is the first report of pyrethroid resistance in populations of L. maculicollis in the Northeastern United States.