The experiment in which diode volt-ampere characteristics are tested via a voltlammetry method is an appropriate teaching content for students in the transition from secondary edueation to higher education due toits simple cireuit ,convenient operation and understandable principle.ln this work , the influences of temperature and meter eonnections in the experiment are studied to help people understand the experimental prineiple as well as improve the teaching quality. lt is suggested that the current flowing through the diode should be limitedto reduce the experimental error introduced by temperature rise.The experimental error is much smaller when the ampere meter is connected outside the voltmeter-diode loop, After math ematieal trealments by introducing the internal resistances of the meters , the experimental results measured when the ampere meter is connec tecinside the voltmeter-diode loop are similar to those when the ampere meter is connected outside the voltmeter. diode loop.The analyses of the experimental results and the oretieal formula show that the ideal current-voltage relationship in positive biased PN junction is not suitable for practical diodes.