This study was conducted to investigate solid-liquid reactions with phase transfer catalysts in an anhydrous system. The halogen exchange between benzyl chloride in the organic phase and potassium bromide (KBr) in the solid phase was carried out at 323 K or 353 K, and the esterification between benzyl chloride and sodium benzoate was carried out at 353 K. Polyethylene glycols with various molecular weights were used as catalysts. When these two reactions were carried out in an anhydrous system, a liquid phase containing polyethylene glycol was formed between the organic liquid phase and the solid phase. The rate of halogen exchange without water was 18 times higher than that with water. In addition, a much smaller amount of KBr was required without water than with water. The reaction rate without water was maximal when the polyethylene glycol had an average molecular weight of 400. This phenomenon could be explained by the increase in solubility of benzyl chloride in polyethylene glycol and the decrease in that of KBr with the increase in the molecular weight of polyethylene glycol. The rate of esterification without water was 9 times higher than that with water and was maximal with polyethylene glycol with an average molecular weight of 200. In conclusion, these two reactions in a solid-liquid system without water occurred by the liquid reactant in the organic phase and the solid reactant being dissolved in a liquid phase containing polyethylene glycol.