The invention discloses a low-grade heat source driven jet refrigeration system and method. The low-grade heat source driven jet refrigeration system comprises: a primary flow input end of an ejector is connected with an output end of a generator, while a secondary flow input end of the ejector is connected with an output end of an evaporator; an output end of the ejector is divided into two branches, and one branch is connected to an input end of a condenser while the other branch is connected to an input end of a booster; an output end of the booster is connected with an input end of the generator; and an output end of the condenser is connected with an input end of the evaporator. The low-grade heat source driven jet refrigeration system has the following beneficial effects: as a mixed flow is re-recycled by the system, lots of heat in the mixed flow can be re-utilized so that a requirement of the system on heat is reduced and a requirement on a heat source is also reduced; as a result, a high dependency characteristic of an ejector air-conditioning system is effectively reduced and the stability of the system is improved.