The invention relates to a fault code detection and recording method of an electronic control unit (ECU) of a vehicle. A fault code shielding parameter is preset in the ECU and contains a plurality of bits; and a one-to-one-correspondence mapping relation between all bits of the fault code shielding parameter and all fault codes of the ECU is formed. The method comprises the following steps that: fault detection is carried out; after occurrence of a fault is detected, a bit corresponding to the fault code in the fault code shielding parameter is searched; according to the numerical value of the searched bit, whether the fault code is recorded is determined; and when the fault code needs to be recorded, the fault code is recorded and stored. In addition, the invention also provides an ECU of a vehicle and a vehicle. After development of the ECU is completed, redundant fault codes of the ECU can be shielded without the need to modify ECU software, thereby avoiding repeated development of the ECU.