Abstract: An antenna device for a radio transmission-reception apparatus is disclosed which comprises an antenna element which is to be electrically and mechanically connected to a printed-circuit board fixed in a housing of the radio transmission-reception apparatus, an inverted U-shaped hollow reinforcement spacer, an antenna cover and a retaining portion formed on the housing. The reinforcement spacer has a hole formed in the top portion thereof a diameter of which is substantially equal to that of the antenna element to slide therethrough, a slit formed continuously from the hole to a base end thereof through which said antenna element can be entered in the reinforcement spacer, and a flange formed around the outer circumference of the base end. The antenna cover is constituted to accommodate therein the antenna element with the reinforcement spacer, and has a flange formed around the circumference of a base end thereof.