A liquid helium, time-of-flight coincidence neutron polarimeter has been developed to measure neutron polarization. The polarizer-analyzer is liquid helium in a specially constructed cryostat. Energy selection is accomplished by time-of-flight techniques and the background is reduced to a negligible amount by requiring fast coincidence between the polarizer-analyzer and the side counters. The counts from both side counters are recorded simultaneously in a 400-channel analyzer by splitting the memory of the analyzer. Measurement of the neutron polarization for the D(d,n) 3He reaction was made using the polarimeter for deuteron bombarding energies between 1.5 and 1.9 MeV at a laboratory angle of 35°. The polarization varies from -16.5 percent at 1.5 MeV to -21.6 percent at 1.9 MeV.