This standard specifies the method for the determination of quaternary ammonium salt content in preservative wood and wood preservatives using an automatic Potentiometric titrator, covering sample preparation, instrumentation, reagent preparation and specific determination steps. It is suitable for the accurate determination of quaternary ammonium salt content in preservative wood and related preservatives, providing a scientific basis for the evaluation of preservative treatment effect. The relevant terms and definitions are quoted in the standard and are operated in accordance with current standards such as GB/T 14019. This document provides an important reference for quality control and research in the wood preservative industry.