In this paper, a novel nanocomposite fulvic acid reduced graphene oxide (FA-rGO) and Co-phthalocyanine nanorods (CoPcNRs) was prepared and used to construct an electrochemical sensor for simultaneous detection of catechol (CC), hydroquinone (HQ), phenol (PN) and p-nitrophenol (p-NP). FA as reductant used to prepare FA-rGO nanocomposite, which fabricated by hydrothermal method and freeze-drying process. The method is environmentally friendly and realizes the gentle reduction of GO. CoPcNRs were synthesized by surfactant-assisted ultrasonic method. The microstructure and morphologies of the as-prepared materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-Vis spectrophotometer. The electrochemical oxidation of CC, HQ, PN and p-NP was investigated using differential pulse voltammetry (DPV). The results show that the FA-rGO/CoPcNRs modified electrode exhibits excellent electrochemical activity toward the simultaneous redox of CC, HQ, PN and p-NP. Under optimal conditions, the linear ranges of CC, HQ, PN and p-NP were 1 mu M-650 mu M, 2 mu M-450 mu M, 2 mu M-160 mu M, 2 mu M-140 mu M, with 0.3 mu M, 0.65 mu M, 0.65 mu Mand 0.65 mu M, respectively. In addition, themodified electrode showed good selectivity, sensitivity and stability. The application in real samples was also evaluated, and the recoveries suggesting that FA-rGO/CoPcNRs nanocomposites could be used as an excellent potential reaction platform for the simultaneous determination of CC, HQ, PN and p-NP in environmental samples. (C) 2019 The Electrochemical Society.