Connection seat and connection structure for coaxial cable

A connection seat includes a base including a top plate and a pedestal connected to each other, a metal member including a body and at least one grounding end, a press cover including a protruding portion, and a flexible concatenation portion connecting the base and the press cover. The base further includes a first trench located on the top plate, a second trench located between the top plate and the pedestal, and a through-hole running through the top plate and the pedestal. A coaxial cable can extend into the base along the first trench, to be detachably mounted to the base. The body extends into the second trench to engage the metal member with the base, and the grounding end extends out of the pedestal. When the concatenation portion is bent such that the press cover covers the top plate, the protruding portion correspondingly protrudes toward the through-hole.