Horse mackerel (Trachurus trachurus) from the fish market in Granada, South Spain, were surveyed for anisakid nematodes. The fish came from fishing ports all over the country. Larval anisakids were found in 39.4% of the fish examined. In all, 26.1% were infected with third-stage larvae (L3s) of Anisakis simplex; 0.3%, with A. physeteris L3s; 31.1%, with Hysterothylacium aduncum L3s; and 1.7%, with fourth-stage larvae (L4s) of Hysterothylacium sp. Horse mackerel from Mediterranean Sea coast ports (South and Southeast Spain) had the lowest levels of infection and those from Cantabrian Sea coast ports (North Spain) had the highest levels. Variations in infection levels with host size (age) and season of capture were surveyed.