A high frequency characteristic measuring device for measuring high frequency characteristics of a high frequency device to be measured by contacting probe needles with the high frequency device to be measured, before mounting of the high frequency device to be measured. The high frequency characteristic measuring device includes an input matching circuit substrate with an input matching circuit thereon, a first coaxial connector electrically connected to the input matching circuit substrate, and first probe needles electrically connected to the input matching circuit substrate. The high frequency characteristic measuring device further includes an output matching circuit substrate with an output matching circuit thereon, a second coaxial connector electrically connected to the output matching circuit substrate, and second probe needles electrically connected to the output matching circuit substrate.