With the rapid development of the integrated and modularized civil aircraft electronic system and the widely use of aircraft data link system, the requirement of the automatic test in aircraft data link system becomes imperative. GUI automatic test is based on HMI. This document introduces an improved GUI automatic test framework based on HMI (Human Machine Interface) which is implemented in civil aircraft data link system. It changes the manual test of internal modules into the automatic test of the functional black box which makes the test more efficient.