To provide a waterfroof connector and an electronic apparatus casing incorporating it, and a combination of the electronic apparatus casing incorporating it and its mating waterproof connector that prevent water or moisture from intruding into contacting areas of contacts of a male and female connecters and enable the correct transmission of data from the apparatus to host equipment.

This invention relates to a male or female waterproof connector 1 which is installed in an electronic apparatus casing of a temperature recorder or the like in a watertight manner; a cylincdrical part having an outer size slightly smaller than the inner size of an insertion hole of the electronic apparatus casing is formed in an insulating main body 5 receiving a contacts 3 to which a signal line is connected; an elastic ring 7 capable of sealing the space between the insertion hole and the cylindrical part in a water tight manner is mounted in the form making one turn around the cylindrical part.