A coaxial connector has a strong structure to avoid structural distortion and looseness comprising a housing, a sliding support, an electric conducting block, a first conducting rod assembly, a first sealing support, a second conducting rod assembly, a second sealing support, a contact piece and a third sealing support, which takes an advantage of good electrical connection formed between the contact piece and the first conducting rod assembly through the electric conducting block to enhance the signal transmission function and to obtain a stable signal without distortion when the coaxial connector is switched from one direction to another direction to transmit signal.