PROBLEM TO BE SOLVED: To provide an oily thickener having high thickening effect on an oily component including silicone oil and allowing formation of an oily composition excellent also in use feeling； a thickening oily composition containing the oily thickener and a liquid oil content； and a cosmetic combined with these oily thickener and thickening oily composition.SOLUTION: An oily thickener consists of a siliconized polysaccharide compound represented by the formula (1) and a silicone emulsifier. (PL is a glucose residue of pullulan, Ris a monovalent hydrocarbon group having a carbon number of 1 to 10, Ris a monovalent hydrocarbon group having a carbon number of 1 to 10 or a siloxy group represented by -OSi(R), Ris a monovalent hydrocarbon group having a carbon number of 1 to 8, n is an integer of 1 to 10, a is 0 or 1, b is 0,1 or 2. The average bond number (substitution degree) of a silicone compound per unit of constituent sugar in the polysaccharide compound is 0.5 to 2.5, and the average molecular weight of the siliconized polysaccharide compound is 50,000 to 10,000,000.)【課題】シリコーン油をはじめとする油性成分に対して高い増粘効果を有し、使用感にも優れる油性組成物を形成し得る油性増粘剤、該油性増粘剤と液状油分とを含有する増粘油性組成物、及びこれら油性増粘剤あるいは増粘油性組成物を配合した化粧料を提供する。【解決手段】式（１）で示されるシリコーン化多糖化合物とシリコーン乳化剤とからなる油性増粘剤。（ＰＬはプルランのグルコース残基、Ｒ1は炭素数１～１０の１価炭化水素基、Ｒ2は炭素数１～１０の１価炭化水素基又は－ＯＳｉ（Ｒ3）3で示されるシロキシ基、Ｒ3は炭素数１～８の１価炭化水素基、ｎは１～１０の整数、ａは０又は１、ｂは０，１又は２。多糖化合物の構成糖１単位当たりのシリコーン化合物の平均結合数（置換度）は０．５～２．５、シリコーン化多糖化合物の平均分子量は５０，０００～１０，０００，０００。）【選択図】なし
