Pollen from five cultivars (cvs.) of pecans [Carya illinoinensis (Wangenh.) K. Koch] was sampled at Brownwood and College Station, Texas, in 1991 and 1992. Samples were analyzed for cytoplasmic lipid classes and constituent fatty acids. Lipid classes in all cvs. included phosphatidyl inasitol, phosphatidyl swine, phosphatidyl choline, phosphatidyl glycerol, phosphatidyl ethanolamine, free fatty acids, and triglycerides. Triglycerides were the predominant class of lipids in all cvs. analyzed. Fatty acids, qualitated and quantitated by gas chromatographic-mass spectral analysis, included palmitie (16:0), stearic (18:0), oleic (18:1), linoleic (18:2), and linolenic (18:3) adds. Quantities of individual and total fatty acids were significantly influenced (P> 0.05) by tree age. Within a uniform age class, quantities of individual and total fatty acids varied greatly and were significantly influenced by cultivar, year, and location as well as by interactions of main effects. The percent composition of individual fatty acids was stable in relation to total fatty acids in the sample, despite wide variation in quantities of fatty acids in different samples. Total fatty acids varied from 2.53% to 0.25% of dry weight. How this large variability in stored energy levels among pollen sources may affect orchard production is discussed.