It is a very essential problem in electromagnetism to solve the distribution of magnetic field generated by current-carrying with the method of Bio-Savart's law .As the magnetic induction intensity dB generated by the current element dl on the current-carrying circular coil at a certain point on the axis is oriented in a three-dimensional space, which leads to the result that students generally think it abstract and difficult to understand . The article takes the magnetic field distribution on the axis of the current-carrying coil as an example,concerning about the magnetic field on the axis of the current-carrying coil is measured by the experimental method of electromagnetic induction.The obtained data charts can visually describe the magnetic distribution characteristics on the axis of the current-carrying circular coil, and the experimental results are very proved of  Biot-Savart law. The formula of magnetic induction intensity on the axis of current-carrying circular coil is applied to the teaching mode of combining new experimental technology with electromagnetics theory in practical teaching, so as to make it abstract.Physical concepts and formulas have become more specific and visualized, and have also received good teaching results.