The invention relates to a portable fast heat dissipation currency detector provided with a cash dispenser capable of separately dispensing authentic currency and counterfeit currency. The currency detector comprises a currency detector body, wherein the currency detector body is provided with a currency input opening, an inner part of the currency detector is provided with a currency twisting assembly and a control module, the currency twisting assembly is connected with the control module via a connecting lever electric motor, the control module is connected with a currency counting and detecting identification device, a currency output part is arranged on the currency detector body, the currency output part comprises an authentic currency output opening and a counterfeit currency outputopening, the authentic currency output opening is arranged on a front part of the currency detector body, the counterfeit currency output opening is arranged on a rear part of the currency detector body and below the currency inlet opening, a currency placement assembly hinged onto the currency detector body is arranged at the currency inlet opening, the authentic currency output opening and thecounterfeit currency output opening are provided with currency receiving assemblies hinged onto the currency detector body, each of the currency placement assembly and the currency receiving assemblyhas a foldable structure, a hollow heat dissipation member is arranged in the currency detector body and is arranged on a side close to the currency twisting assembly, and the hollow heat dissipationmember is arranged parallel to the currency twisting assembly from front to back.