Disclosed is a manhole type omnidirectional antenna having a relatively small angle between a main beam direction and the Earth's surface and exhibiting omnidirectional characteristics to allow long-range communication, wherein the manhole type omnidirectional antenna includes a manhole cover installed in a manhole in the Earth's surface; a main body installed in a cavity of an upper surface of the manhole cover and configured to convert an electrical signal into an electromagnetic wave to wirelessly communicate with a gateway separated from the manhole cover; and a radome inserted into the cavity to cover the main body.