A package substrate includes: an insulating substrate, a first and a second soldering pads spacedly disposed on a first surface of the insulating substrate, a first and a second electrodes spacedly disposed on an opposite second surface of the insulting substrate. The first and the second soldering pads are electrically connected to the first and the second electrodes respectively. Moreover, a first and a second grooves are defined on the first surface of the insulating substrate, the first and the second grooves are spaced from each other and disposed between the first and the second soldering pads. The invention further provides a LED flip chip package structure including the package substrate, a LED flip chip and fluorescent glue. The invention adds the grooves in the spacing between the soldering pads as a buffer space for melted solder flowing during reflow soldering process and therefore can relieve short-circuit phenomenon.