This paper describes the development of an electrochemical sensor coupled to flow injection analysis system for the detection of pesticides. The proposed sensor was prepared using a carbon paste electrode modified with hemin and nickel (II) 1,48,11,15,18,22,25-octabutoxy-29H, 31H-phthalocyanine complex as possible catalysts P450 enzyme and graphene oxide in order to improve the sensitivity of the sensor. In the first place, we used the cyclic voltammetry in a response range of -0.2 to 1 V to monitor the electrochemical response of each pesticide. In optimized conditions, an amperometric study of the proposed sensor was conducted applying the potential of 0.45 and 0.8 V for the redox reaction of carbofuran-phenol and diuron. The system showed a linear response in a concentration range between 5.0 × 10-6and 1.4 × 10-4and 5.0 × 10-5and 1.0 × 10-3mol L-1and detection limit of 1.7 × 10-6and 2.0 × 10-5mol L-1for carbofuran and diuron, respectively. The proposed sensor was applied in soil and carrot samples and the results obtained in the recovery study were close to 100%. The reliability of the proposed sensor was confirmed after comparing the results with those obtained in the comparative method (HPLC).