<p>Anthelmintic resistance has prompted the search for alternative control strategies, such as the use of plant-derived compounds and biological control with nematophagous fungi. The aim of the present study was to evaluate the in vitro anthelmintic effect of linalool and its association with the fungus <i>Arthrobotrys cladodes</i> on gastrointestinal nematodes of sheep. The larvicidal activity of linalool, alone and in combination with <i>A. cladodes</i> conidia, was assessed using the Larval Motility Inhibition Test (LMIT) on infective larvae (L3). Ten (10) experimental groups were designed, each with eight replicates, comprising treatments with linalool and <i>A. cladodes</i> conidia, alone and in combination, as well as ivermectin (positive control) and distilled water (negative control). Larval motility was evaluated under optical microscopy after 1, 7, and 14 days of exposure. A significant reduction (<i>p</i> ≤ 0.05) in the number of L3 larvae was observed in the groups treated with linalool combined with <i>A. cladodes</i> (G7–G10) compared to the negative control group (G1), starting at 24&#xa0;h and reaching 100% reduction after 14 days. The groups treated only with <i>A. cladodes</i> conidia (G3 and G4) showed less effective reductions compared to the combined treatments. The larvicidal activity of the groups treated solely with linalool (G5 and G6) did not differ statistically (<i>p</i> &gt; 0.05) from those treated with the fungus and linalool. It is concluded that the combination of linalool and <i>A. cladodes</i> conidia exhibits anthelmintic activity against gastrointestinal nematodes of sheep, demonstrating a synergistic interaction between the nematophagous fungus and the monoterpene.</p>