<p>In the current study, a magnetic nanocomposite composed of vegetable oil-based n-octadecyl acrylate and acrylic acid has been synthesized and utilized for magnetic solid-phase extraction. This study aims to create a separable and eco-friendly nanocomposite for water treatment. A prepared magnetic sorbent, coupled with high-performance liquid chromatography, was used to extract, separate, and determine the selected triazole fungicides, including propiconazole and tebuconazole, in water samples. Successful synthesis was confirmed through nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, Brunauer–Emmett–Teller analysis, X-ray diffraction analysis, scanning electron microscopy, energy dispersive X-ray Spectroscopy, thermogravimetric analysis, and a vibrating sample magnetometer. To improve the extraction efficiency, the extraction parameters, including sorbent dosage, type and volume of desorption solvent, extraction and desorption times, pH of the sample solution, and salt effect, were optimized. Under the optimized condition, the method shows good linearity (<i>r</i>² &gt; 0.9960) in the 1–500 µg L⁻¹ range and limits of detection of 0.28 and 0.25 µg L⁻¹ for tebuconazole and propiconazole, respectively. Enrichment factors of 42 for tebuconazole and 38 for propiconazole, with absolute recoveries of 63% (tebuconazole) and 57% (propiconazole), confirmed the good accuracy and efficiency of the method. Low relative standard deviation values for tebuconazole and propiconazole, ranging from 1.3% to 3.4% for tebuconazole and 2.3% to 5.9% for propiconazole, indicate high precision. Moreover, the method’s applicability was demonstrated by determining the target analytes in agricultural products, including tomatoes, carrots, apples, and oranges. In conclusion, the proposed method was successful at quantifying triazole fungicides in water samples.</p> Graphical Abstract <p></p>