A package structure of a common-source common-gate gallium nitride field-effect transistor is disclosed, including a lead frame. A gallium nitride field-effect transistor and a metal oxide semiconductor are directly disposed on the lead frame. The gallium nitride field-effect transistor includes a first matrix directly disposed on the lead frame. A first drain, a first gate, and a first source are disposed on a surface side of the first matrix, and the first drain and the first gate are separately electrically connected to the lead frame. The metal oxide semiconductor includes a second matrix directly disposed on the lead frame. A second drain, a second gate, and a second source are disposed on a surface side of the second matrix, the second drain is directly electrically connected to the first source, and the second gate and the second source are separately electrically connected to the lead frame.