The present application discloses a method for locating an open circuit failure point of a test structure, which includes the following steps: step 1: providing a sample formed with a test structure, a first metal layer pattern and a second metal layer pattern of the test structure forming a series resistor structure through each via; step 2: performing a first active voltage contrast test to the sample to show an open circuit point and making a first scratch mark at an adjacent position of the open circuit point; step 3: forming a coating mark at the first scratch mark on the sample; step 4: performing a second active voltage contrast test to the sample to show the open circuit point and locating a relative position of the open circuit point by using a position of the coating mark as a reference position.