Provided is a thickening stabilizer that thickens, gels or stabilizes the flowable organic substance to a desired viscosity. The thickening stabilizer of the present invention comprises the compound (1) represented by the formula (i) and the compound (2) represented by the formula (ii) in an amount of 95/5 to 25/75 (the former / the latter (moles). It is characterized by containing in the ratio of ratio). In the formula (i), the four R 1 ''s are the same and each represent an aliphatic hydrocarbon group having 12 to 18 carbon atoms, and in the formula (ii), the four R 2'' s are the same. Indicates a hydrocarbon group. [Chemical formula 1]流動性有機物質を所望の粘度に増粘、ゲル化、又は安定化する増粘安定剤を提供する。 本発明の増粘安定剤は、式（i）で表される化合物（１）、及び式（ii）で表される化合物（２）を、９５／５～２５／７５（前者／後者（モル比））の割合で含有することを特徴とする。尚、式（i）中、４つのＲ1は同一に炭素数１２～１８の脂肪族炭化水素基を示し、式（ii）中、４つのＲ2は同一に炭素数４～１０の脂肪族炭化水素基を示す。【化１】
