An apparatus for testing a circuit board of a battery management system, wherein the circuit board includes a first resistor; a first capacitor; a second resistor; a second capacitor; a first test point connected in common to one end of the first resistor, one end of the first capacitor and one end of the second resistor; a second test point connected in common to the other end of the second resistor and one end of the second capacitor; a third test point connected to the other end of the first resistor; and a fourth test point connected in common to the other end of the first capacitor and the other end of the second capacitor, the apparatus comprising: a voltage source; a first voltage sensor configured to detect a first diagnosis voltage generated between the first test point and the fourth test point; and a second voltage sensor configured to detect a second diagnosis voltage generated between the second test point and the fourth test point; and a control unit operably coupled to the voltage source, the first voltage sensor and the second voltage sensor and configured to control the voltage source to apply a test voltage onto the third test point, and record a first time point at which the first diagnosis voltage reaches a threshold voltage which is preset as being lower than the test voltage, and record a second time point when the second diagnosis voltage reaches the threshold voltage, to determine that both the first capacitor and the second capacitor do not have an open-circuit fault in response to a first elapsed period from an initial time point to the first time point being equal to or longer than a preset first threshold period, wherein the initial time point is a time point when the test voltage starts to be applied onto the third test point, and to determine that at least the second capacitor among the first capacitor and the second capacitor has the open-circuit fault, when the first time point and the second time point are equal to each other. a voltage source; a first voltage sensor configured to detect a first diagnosis voltage generated between the first test point and the fourth test point; and a second voltage sensor configured to detect a second diagnosis voltage generated between the second test point and the fourth test point; and a control unit operably coupled to the voltage source, the first voltage sensor and the second voltage sensor and configured to control the voltage source to apply a test voltage onto the third test point, and record a first time point at which the first diagnosis voltage reaches a threshold voltage which is preset as being lower than the test voltage, and record a second time point when the second diagnosis voltage reaches the threshold voltage, to determine that both the first capacitor and the second capacitor do not have an open-circuit fault in response to a first elapsed period from an initial time point to the first time point being equal to or longer than a preset first threshold period, wherein the initial time point is a time point when the test voltage starts to be applied onto the third test point, and to determine that at least the second capacitor among the first capacitor and the second capacitor has the open-circuit fault, when the first time point and the second time point are equal to each other.