Scanning electron microscopic observations were made on the early third stage (eL3) larvae of Gnathostoma spinigerum (Sakolnakhon, northeast Thailand) from 3-week-old infected cyclops (Mesocyclops leuckarti). The morphological surfaces of the anterior end, head spine, body cuticle, amphid, papillae, posterior end of larvae were described and compared with the advance third-stage (aL3) larvae.