Polycarbosilane (PCS) has been widely used to fabricate silicon carbide (SiC) fibers via pyrolysis. In this paper, for improving the morphology of SiC fibers, tetraethyl orthosilicate (TEOS, m = 1 g, 3 g and 5 g, respectively) was added into the PCS precursor solution (containing 1.5 g PCS). The continuous fibers have been prepared by electrospinning, and then the SiC fibers were synthesized by calcination at 1300 ℃, 1400 ℃ and 1600 ℃ for 4 h respectively with a heating rate of 10 ℃/min in flowing nitrogen (N₂). The morphologies of the fibers were investigated by the scanning electron microscope (SEM) and it could be seen that the crystallinity of the SiC fibers was lower, the length of the SiC fibers was increased, and the diameter was uniform with the increase of the addition amount of TEOS.