The first results from a deployment of four instruments on the floor of the Beaufort Sea in March 1990 are presented. The instruments recorded pressure fluctuations in the band from 0.0005 to 8 Hz during a 2-week period. The pressure spectra derived from these measurements show very low energy in the microseism peak near 0.1 Hz in comparison with measurements from the Pacific or Atlantic seafloor. The microseism band shows a series of spectral peaks and valleys likely associated with the modes of the ocean–seafloor Rayleigh wave waveguide. The shape of the microseism peak is remarkably stable during the experiment although the amplitude varies by about 10 dB. The signals are very coherent between adjacent instruments and suggest propagation in the microseism band from a source in the Gulf of Alaska. The pressure spectra rise rapidly toward lower frequency below 0.02 Hz, but Arctic spectra are less energetic than spectra from sites on either Pacific or Atlantic seafloors at all frequencies. The long period energy appears to be related to flexural-gravity waves on the ocean surface. The pressure measurements predict amplitudes for these waves in general agreement with previous tilt and displacement measurements made on the ice.