4,5-Bis(dodecylthio)- and 4,5-bis(octadecylthio)-4 ',5 '-bis(methoxycarbonyl)tetrathiafulvalenes (1a and 1b) exhibit gelling ability for hexane, cyclohexane, decalin, and diethyl ether to form electroactive fibrous material with 5-10 mu m diameters. The doping of bunches of fibers with iodine shows moderate electrical conductivities (sigma(rt) = 2.9 x 10(-3) -2.0 x 10(-5) S cm(-1)).