Dicyclopentadiene type unsaturated polyester resins(DCPD-type-UPR) are synthesized by hydrolysis addition method with phosphoric acid and adipic acid as modifiers.The resins contain DCPD of 27.5% and the comprehensive properties of resins are superior. Results show that the use of phosphoric acid gives a less coloration of, and a transparent product ; adding adipic acid can effectively improve brittleness of the resins.The effects of DCPD and adipic acid content on product properties are investigated and the properties of DCPD-type-UPR and 191^# UPR are cont rasted.