We examined the movement of [³H]-palmitate across giant sarcolemmal vesicles prepared from red and white muscle of rainbow trout (Oncorhynchus mykiss). Red and white muscle fatty acid carriers have similar affinities for palmitate (apparent K_m = 26±6 and 33±8 nM, respectively); however, red muscle has higher maximal uptake compared to white muscle (V_max = 476±41 versus 229±23 pmol^.mg^-1 protein^.s^-1, respectively). Phloretin (250 µM) inhibited palmitate influx into red and white muscle vesicles by ~40%, HgCl₂ (2.5 mM) inhibited palmitate uptake by 20 to 30%, and the anion-exchange inhibitor, 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS; 250 µM) inhibited palmitate influx into red and white muscle vesicles by ~15 and 30%, respectively. Western blot analysis of red and white muscle vesicles did not detect a mammalian-type fatty acid transporter (FAT); however, preincubation of vesicles with sulfo-N-succinimidyloleate, a specific inhibitor of FAT in rats, reduced palmitate uptake into red and white muscle vesicles by ~15 and 25%, respectively. A mammalian-type plasma membrane fatty acid binding protein was identified in trout muscle using western blotting, but the protein differed in size between red and white muscle. At low concentrations of free palmitate (2.5 nM), adding high concentrations (111 µM total) of oleate (18:0) caused ~50% reduction in palmitate uptake by red and white muscle vesicles, but high concentrations (100 µM) of octanoate (8:0) caused no inhibition of uptake. Five days of aerobic swimming at ~2 bl^.s^-1 and 9 days of chronic cortisol elevation in vivo, both of which stimulate lipid metabolism, had no effect on the rate of palmitate movement into red or white muscle vesicles.