A test circuit transmits input data of a test vector to a data distribution circuit using an input of a test bus, and transmits the input data of the test vector to a scan input channel in a circuit under test using the data distribution circuit. After scan of the circuit under test is completed, output data of the test vector on a scan output channel in the circuit under test is transmitted to an output of the test bus using the data distribution circuit, to complete testing of the circuit under test. A dynamic correspondence between the data distribution circuit and the test bus may be configured based on a specific test solution, so that a test resource can be dynamically allocated.