Highly ordered and uniformly sized mesoporous carbon nanospheres (MCNs) were synthesized by a low-concentration hydrothermal method. Then, a polymeric ionic liquid (PIL) was incorporated into the MCNs by a hydrothermal method to form (polymeric ionic liquid)/(mesoporous carbon nanospheres) (PIL-MCNs) nanocomposites. The MCNs and PIL-MCNs were characterized by transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The characterization results demonstrate that the materials are highly ordered and possess uniform size. The PIL-MCNs modified glassy carbon electrode (GCE) exhibits good electrocatalytic properties to the redox of hydroquinone (HQ), catechol (CC), and paracetamol (PA), and typical oxidation peak potentials are of 0.214 V, 0.321 V and 0.509 V (vs. Ag/AgCl), respectively. The PIL-MCNs/CS/GCE was used to the simultaneous determination of HQ and CC, and also the detection of PA. Under optimal conditions, the responses to HQ, CC and PA are linear in 10-350 mu M, 10-400 mu M and 1-300 mu M, and the detection limits are 1.39, 0.62, and 0.164 mu M (S/N = 3). Satisfactory results were obtained in determination of HQ, CC simultaneously in spiked tap water samples, and in the detection of PA in paracetamol tablets. In addition, the sensor displays satisfied selectivity, good reproducibility and stability. (C) 2020 Elsevier B.V. All rights reserved.