To obtain solubilizer which is excellent in solubilization performance, and also can prepare an aromatic agent excellent in time-stability and particularly freezing stability.

This solubilizer contains a nonionic surfactant represented by the formula (1), and an alkylene oxide addition product of fat and oil having a hydroxyl group, and/or an ethylene oxide addition product of a fatty acid ester product of a polyhydric alcohol or its intermolecular dehydration product. formula (1) R1O-[(C2H4O)p-(A1O)q]-(C2H4O)r-(A2O)s-H [wherein R1 is an 8-24C alkyl group, alkenyl group, or the like; A1 and A2 are each a 3 or 4C alkylene group; (p) is 0 to 4; (q) is 1 to 3; (r) is 1 to 80; (s) is an integer of 0, or one or more from 0 to 10; (p+q+r+s) are integers from 3 to 81; and (p+r)/(p+q+r+s) is 0.5 or more].