Fixing structure and ventilation fan therefor

A ventilation fan mounted on a ceiling, the ceiling comprising a mounting vent, a first side and a second side, the ventilation fan comprising:

• a case disposed on the first side of the ceiling and comprising a first vent, wherein the first vent is adjacent to the mounting vent of the ceiling;
• a fan assembly accommodated in the case;
• and
• an outer cover disposed on the second side of the ceiling and comprising:
• at least one fixing structure comprising:
• a base;
• a first fastener disposed on the base and comprising a first hook portion, a first accommodation portion and a first opening portion;
• and
• a second fastener disposed on the base and comprising a second hook portion, a second accommodation portion and a second opening portion;
• wherein a guiding groove is defined between the first fastener and the second fastener and is in communication with the first fastener and the second fastener, and a positioning channel is defined by the guiding groove, the first accommodation portion and the second accommodation portion, collaboratively, wherein the first opening portion and the second opening portion are located on the opposite sides of the positioning channel, respectively;
• and
• at least one elastic element being fixed with the at least one fixing structure and extended through the first vent of the case to be connected to the case.