Disclosed is a method for acquiring an altitude correction coefficient, comprising: acquiring an initial value of an altitude correction coefficient self-learning filter when a preset event occurs to a vehicle engine, the preset event includes a power-off event, a power-on event, and an unexpected power-down event; evaluating whether the vehicle satisfies a preset self-learning enabling condition, in accordance with an engine rotation speed, a vehicle speed, and status information of designated devices; enabling the altitude correction coefficient self-learning filter when the vehicle satisfies the preset self-learning enabling condition; determining an input of the altitude correction coefficient self-learning filter at least in accordance with operating states of a manifold pressure sensor and a stepping motor; and obtaining a current altitude correction coefficient by self-learning the altitude correction coefficient applying the altitude correction coefficient self-learning filter in accordance with the initial value of the altitude correction coefficient self-learning filter and the input of the altitude correction coefficient self-learning filter. An apparatus for acquiring an altitude correction coefficient is also disclosed. The above method and apparatus improve the accuracy of the altitude correction coefficient and enhance the idling satiability.