PROBLEM TO BE SOLVED: To provide a lubricant composition for a refrigerating machine that has excellent thermal stability and chemical stability even when including a fluorescent agent for refrigerant leakage detection.SOLUTION: A lubricant composition for a refrigerating machine comprises combining an additive into a base oil, wherein the additive is a coumarin compound. In an open type automotive air conditioning, an electric automotive air conditioning, a gas heat pump, an air conditioning, a refrigerator, a vending machine, a showcase, a hot water supply system, and a freezer such as a refrigeration and heating system that use the lubricant composition for a refrigerating machine, leakage detection of a refrigerant can be performed stably for a long period of time. Therefore, when an unsaturated fluorocarbon refrigerant with low stability is used for these various equipment, the lubricant composition for a refrigerating machine is extremely effective.