A very sensitive voltammetric method for the determination of an endocrine disruptor Chlorpyrifos (CP) insecticide at ng mL(-1) level was described. The pesticide was accumulated at a hanging mercury drop electrode (HMDE) and a well-resolved reduction peak was observed at -1.2 V (vs. Ag/AgCl) in pH: 2.0 media containing 5% aqueous ethanol solution. A systematic investigation of the solution parameters and operational parameters which affect the stripping response were carried out with differential pulse voltammetry. With an accumulation potential of -0.5 V and an accumulation time of 60 s, the detection and quantification limits were found to be 0.14 and 0.45 ng mL(-1), respectively. The remarkable sensitivity of the method was attributed to a catalytic process as concluded from cyclic voltammetry. The degree of interference from diverse ions and some other pesticides on the differential pulse stripping signal for CP was evaluated. The method developed was adapted for wine samples. The matrix effect of red wine was eliminated by means of liquid-liquid extraction (LLE) followed by solid-phase extraction (SPE) with satisfactory recovery values. This method offers a very sensitive and inexpensive way for determining CP residues in red wines.