Chemical Oxygen Demand (COD) is referring to the total amount of oxygen used for a chemical oxidation of organic compounds in a water sample. COD stands as an important tool for water safety and water quality standard. Fast-scan cyclic voltammetry (FSCV) has been reported as a simple and a rapid method for electrochemical measurements, particularly for neurotransmitter compounds in brain and biological systems. The main explicit characteristics of FSCV comes from the usage of small volumes of analytes and by adapting carbon-fiber microelectrode as a working electrode with a scan rate of milliseconds. In this research project, FSCV has shown promising results as an alternative method that correlates the COD of traditional measurements. Traditionally, COD is more often estimated using oxidizing agents and toxic chemical reagents that have a serious environmental impact on lifecycle. Unlike traditional oxidation methods, FSCV was used as a powerful an electrochemical tool that allows for measuring COD of Iceberg lettuce washing water samples without using any oxidizing or toxic reagents in few minutes. In addition, FSCV measurements showed a high recovery percentage for both batches, low organic materials, and high organic materials. FSCV provides a fast and reliable platform to measure all chemically oxidizable organic compounds in lettuce washing water samples, which is directly related to COD with an environmentally friendly model based on the oxidation potential.