Disclosed is an oil-in-water emulsion sunscreen cosmetic composition which has improved ultraviolet blocking capability by containing a large amount of an ultraviolet absorbent, while having excellent emulsion stability and good usability. Specifically disclosed is an oil-in-water emulsion sunscreen cosmetic composition which is characterized by containing (A) 1-7.5% by mass of octyl methoxycinnamate, (B) 0.5-4% by mass of t-butyt methoxybenzoyl methane and/or 2-hydroxy-4-methoxybenzophenone, (C) 0.5-3% by mass of a polyoxyethylexe-polyoxyalkylene alkyl ether block polymer having a specific structure and (D) not less than 10% by mass of a nonpolar oil relative to the total amount of the oil component. The oil-in-water emulsion sunscreen cosmetic composition is also characterized by having an average emulsion particle diameter of not more than 700 nm.자외선 흡수제를 고배합해서 자외선 방어능을 향상시킴과 아울러 유화 안정성이 뛰어나고, 또한 사용성도 양호한 수중 유형 유화 선스크린 화장료를 제공하는 것을 목적으로 한다. 본 발명은 (A) 1～7.5질량%의 옥틸메톡시신나메이트, (B) 0.5～4질량%의 t-부틸메톡시디벤조일메탄 및/또는 2-히드록시-4-메톡시벤조페논, (C) 0.5～3질량%의 특정 구조의 폴리옥시에틸렌·폴리옥시알킬렌알킬에테르 블록 폴리머, 및 (D) 총 유분량에 대하여 10질량% 이상의 비극성유를 함유하고, 평균 유화 입자 지름이 700㎚ 이하인 것을 특징으로 하는 수중 유형 선스크린 화장료를 제공한다.
