The embodiment of the invention provides a method for detecting circuit parameters, which comprises the following steps that: a test circuit selects at least two nodes in a circuit to be detected; when the circuit to be detected is in a power-on working state, the test circuit measures working voltage values of the nodes; when the circuit to be detected is in a power-off state, the test circuit provides testing current for the nodes to form an electrically connected access between the nodes, and the test circuit calculates testing current values and testing voltage values of the nodes; and according to the working voltage values, the testing current values and the testing voltage values of the nodes, the working current value of the circuit to be detected in a power-on normal working state is calculated. The detection method and the device using the method provided by the embodiment of the invention overcome the defect that the physical structure and appearance of a circuit of equipment are destroyed in the testing of the prior art, and are well suitable for detecting parameters of circuits of electronic devices such as chips and the like in the on-line working state.