A securing mechanism includes a first securing unit fixedly disposed on a first component of an electronic device case, and a second securing unit fixedly disposed on a second component for securing the second component to the first component in a first direction. The first securing unit includes a fixture board, a limiting structure and a biasing structure. When the second securing unit extends in the first direction through an engaging through hole in the fixture board, the biasing structure biases the second securing unit in a second direction opposite to the first direction, and the second securing unit engages the limiting structure. As a result, movement of the second securing unit in a direction toward the engaging through hole is limited.