A test strip and a detecting device are disclosed. The test strip can be used with an electrochemical instrument to accurately detect the viscosity and concentration of an analyte of a specimen. The test strip includes a first specimen path, a first electrode set, a redox reagent, a second specimen path, a second electrode set, and a reaction reagent. The redox reagent includes at least a redox pair. When the specimen enters the first specimen path, the redox pair dissolves and generates an electrochemical redox reaction for obtaining a flow time of the specimen. When the specimen enters the second specimen path, the reaction reagent is used to obtain the analyte concentration of the specimen, and the concentration of the analyte can be corrected by the flow time.