Provided is a thickening stabilizer which thickens a flowable organic substance to a desired viscosity and makes the organic substance to gel or stabilize. The thickening stabilizer of the present invention is characterized by comprising a compound (1) represented by formula (i) and a compound (2) represented by formula (ii) in a ratio of 95/5 to 25/75 (former/latter (by mole)). In formula (i), the four R1's are the same and represent a C12-18 aliphatic hydrocarbon group. In formula (ii), the four R2's are the same and represent a C4-10 aliphatic hydrocarbon group.本發明提供一種將流動性有機物質予以增黏、膠化、或安定化為所需的黏度之增黏安定劑。本發明的增黏安定劑，其特徵為：含有95/5~25/75(式(i)所示化合物(1)/式(ii)所示化合物(2)(莫耳比))之比例的式(i)所示之化合物(1)、及式(ii)所示之化合物(2)。其中，式(i)中，4個R1表示相同之碳數12~18的脂肪族烴基，式(ii)中，4個R2表示相同之碳數4~10的脂肪族烴基。
