Casing and electronic device

A casing, adapted to a board having a first air vent and a second air vent, comprising:

• a base plate having a first side and a second side opposite to each other, and a third side and a fourth side opposite to each other and connected between the first side and the second side;
• a first side plate and a second side plate provided on the first side and the second side of the base plate, respectively, with both the first side plate and the second side plate having hollowed-out patterns, and after the board being fixed in the casing, the first side plate being opposite to the first air vent of the board, and the second side plate being opposite to the second air vent of the board;
• a connection backplate provided on the fourth side of the base plate;
• and
• at least one insert plate provided on the base plate, with an extension direction in which the insert plate extends intersecting with an extension direction in which the third side of the base plate extends.