Abstract: Different associated effects have the influence on the Hall voltage measured in the experiment of Hall effect，such as the Ettinghausen，Nernst，Righi-Ledue，IR drop，thermoelectric drop. In fact，geomagnetic filed also has the effect on the measurement of the Hall voltage. This study has shown that these associated effects could be eliminated by the method of symmetric measurement except the Ettinghausen effect. The influence of IR drop is prominent，and the influence of thermoelectric drop and Geomagnetic filed effects take the second place，while the contributions of the Nernst and Righi-Ledue effects could be ignored. Moreover，the Horizontal component of the geomagnetic filed in Shangrao，measured by the experiment of Hall effect，is about 30.6 μT.

Key words: Hall effect, IR drop, horizontal component of the geomagnetic filed