This study determined the chemical composition of essential oils isolated from Zanthoxylum monophyllum (Lam.) P. Wilson, Z. rhoifolium Lam., and Z. fagara (L.) Sarg. fruits by steam distillation, as well as testing antifungal and insecticidal activities of essential oils as potential pesticides. Gas chromatography-mass spectrometry (GC/MS) analysis identified 57 compounds. The main constituents in Z. rhoifolium oil were β-Myrcene (59.03%), β-phellandrene (21.47%), and germacrene D (9.28%) , the major constituents of Z. monophyllum oil were sabinene (25.71%), 1,8-cineole (9.19%), and cis-4-thujanol (9.19%), whereas fruit oil of Z. fagara mainly contained germacrene D-4-ol (21.1%), elemol (8.35%), and α-cadinol (8.22%). Zanthoxylum fagara showed the highest activity on Colletotrichum acutatum Simmonds (EC50 153.9 μL L-1 air), and Z. monophyllum was the most active against Fusarium oxysporum Schlechtend: Fr. f. sp. lycopersici (EC50 140.1 μL L-1 air). Zanthoxylum monophyllum essential oil showed significant fumigant activity against Sitophilus oryzae (L.). This study demonstrated that Zanthoxylum essential oils exhibit important fungicidal activity on F. oxysporum and C. acutatum, which could become an alternative to synthetic fungicides to control plant fungal diseases, and Z. monophyllum oil is a potential fumigant against S. oryzae.