A power tube connection structure includes a substrate, a printed circuit board, and a power tube, where a through groove allowing the power tube to pass through is cut into the printed circuit board, a mounting groove is cut into the upper surface of the substrate at a location corresponding to the through groove, one end of the power tube extends through the through groove, and is welded onto a bottom face of the mounting groove, the end of the power tube that extends into the mounting groove abuts onto a side wall of the mounting groove close to an output end of the power amplifier, and a solder flux escape channel is made into the side wall of the mounting groove close to the output end of the power amplifier.