The abuse of organophosphate pesticides causes serious threats to human health, which threatens approximately 3 million people and leads to more than 2000 deaths each year. Therefore, it is necessary to determine the residue of fenitrothion (FT) in environmental and food samples. Herein, we developed a non-enzymatic electrochemical sensor with differential pulse voltammetry signal output to determine FT in model solutions and spiked samples. Delicately, the sensor was designed based on the fabrication of hydrothermally synthesized titanium-based metal-organic frameworks (MOFs) material (NH₂-MIL-125(Ti))/reduced graphene oxide (RGO) (NH₂-MIL-125(Ti)/RGO) nanocomposites for better target enrichment and electron transfer. The peak response of differential pulse voltammetry for FT under optimized conditions was linear in the range of 0.072–18 μM with the logarithm of concentrations, and the detection limit was 0.0338 μM. The fabricated sensor also demonstrated high stability and reproducibility. Moreover, it exhibited excellent sensing performances for FT in spiked agricultural products. The convenient fabrication method of NH₂-MIL-125(Ti)/RGO opens up a new approach for the rational design of non-enzymatic detection methods for pesticides.