Sydney Coalfield of Nova Scotia is one of the largest coal basins in eastern Canada and to date has produced 342 million tons of bituminous coal. Production for 1988 was 2.9 million metric tons. Eleven of 22 coal seams of the coalfield were investigated for uranium content and variation, using delayed neutron activation methods for accuracy and precision. At this level of sampling, no systematic variation was detected between uranium concentration and age of coals, but the data indicate that the younger, thick seams (>35 cm) are on average somewhat richer than their older counterparts; the thick seams on average have one-tenth the uranium concentration of the thin seams; lateral uranium variation in a seam is large; seams show distinct trends described by relative enrichmentldepletion patterns in top/bottom coal; and no secondary (epigenetic) uranium enrichment is evident. The best available mean estimate for the entire coalfield is 0.51 ± 0.99 ppm U, an estimate whose variance requires better circumscription. Sydney Coalfield is uranium-poor in comparison with some other coalfields of the same age, and depleted relative to the crustal abundance of 2.7 ppm U. Uranium variation is related to the depositional conditions, controlled by monsoonal changes (within-seam variation) and tectonic instability (between-seam variation) that prevailed during the life of the Sydney Basin. The syngenetic variation was probably modified as a result of coalification, a process that probably was also responsible for uranium-poor coals in Sydney. Uranium release into the environment from coal-fired power plants or from open-air coal storage is mentioned as potential pollution.