The water-based phenolic resin for rock-wool adhesive was prepared by a process of adding the modifiacer in a cold physical mixing method after polycondensation reaction.The influence of modifier’s additive amount and mode on the phenolic resin were investigated.Aiming at the effective solid content,the free phenol/aldehyde content,the viscosity and the curing property of phenolic resin,the water-based phenolic resin for rock-wool adhesive was optimized.The results showed that the comprehensive performance of the water-based phenolic resin for rock-wool adhesive was the best when the amount of urea was 12%.