An amperometric sensor for detection of toxin aflatoxin B1 from aspergillus flavus based on conducting polyaniline probe using monoclonal anti-aflatoxin B1 (Mc-IgGs-a-AFB1) antibodies after activation with 3% Bovine Serum Albumin (BSA) through electrochemical polymerization has been proposed. The electrode was fabricated by immobilizing Mc-IgGs-a-AFB1 antibodies molecules onto electrode surface and characterized by cyclic voltammetry (CV), scanning electron microscopy (SEM) and fourier transform infrared spectroscopic (FT-IR) etc. The proposed amperometric immune-sensor has demonstrated excellent electro-analytical properties relative to Aflatoxin B1 in a linear range from 0.20 to 1.30 AngmL -1 with a relatively low detection limit of 0.059 AngmL -1 . The present study will help in improving for quantitative determination of mycotoxins in food samples may provide significant improvements in quality control of food safety through a simple, rapid, and sensitive testing system for agricultural products monitoring.