The traditional Hall effect experimental device for measuring the internal magnetic field of energized solenoids was improved．On the basis of not affecting the original experimental content，the application of the experimental device was expanded．The magnetic field distribution of different solenoid and the influence of solenoid parameters on its magnetic field could be studied． It was a very good innovation and attempt to organically combine basic experimental projects with hands-on ability and scientific research ability training through the improvement and expansion of existing experimental devices．