The invention relates to the technical field of medical detection and particularly relates to a sweat lactic acid rapid detection device. The device comprises a flexible substrate layer, an electrode layer, an isolation layer and an electronically monitoring layer. The flexible substrate layer is made of a porous flexible material. The electrode layer comprises a counter electrode, a work electrode, a reference electrode and a reaction chamber. The work electrode comprises a second carbon paste lead, a carbon paste electrode III and a reaction electrode. The reaction electrode comprises an oxidase layer and a three-dimensional graphene composite material layer. The three-dimensional graphene composite material layer is prepared from nanometer TiO2 uniformly dispersed on graphene. The three-dimensional graphene composite material layer has a hollow microsphere network structure having pore size distribution of 20nm-40nm and a specific surface area of 1500 m<2>/g-1650 m<2>/g. The isolation layer is bonded to an insulation layer. The electronically monitoring layer comprises a voltage control unit, a current measurement unit and a data finishing unit. The detection device is free of blood sampling, can continuously monitor and detect the amount of human lactic acid and has the characteristics of high detection sensitivity, strong stability and carrying convenience.