Silica gel high-performance thin-layer chromatography-densitometry was used to examine neutral lipid (NL) and phospholipid content in different organ systems of Biomphalaria glabrata snails infected with the parasite Schistosoma mansoni. NLs were determined using petroleum ether-diethyl ether-glacial acetic acid (80:20:1) mobile phase, phosphomolybdic acid detection reagent, and scanning at 610 nm, and phospholipids with chloroform-methanol-water (65:25:4) mobile phase, cupric sulfate-phosphoric acid detection reagent, and scanning at 370 nm. Considerable differences were found in both the NL and phospholipid fractions in the organ systems examined (visceral mass, digestive-gonad gland (DGG), and head-foot region) as a function of the S. mansoni infection. Reasons for these findings probably relate to the metabolic needs of the infected snails.