Test auxiliary device

A test auxiliary device for testing a portable data terminal having a plurality of sensors includes a base, a carrying unit, a driving unit, and a controlling unit. The carrying unit is disposed on the base and includes a carrying platform and a carrying base. The carrying platform and the carrying base form a first angle and a second angle with the base, respectively, and thereby together form a compound slope. The driving unit drives the carrying unit to move, allowing the carrying platform to move with acceleration and at an angular velocity. The controlling unit receives sensing values generated by the sensors, respectively. The test auxiliary device further includes a test matching unit for testing the sensors in operation. Accordingly, the test auxiliary device assists users in determining whether the sensors of the portable data terminal are functioning well.