The experimental study on negative capacitance(NC) of various light-emitting diodes(LEDs) was presented.Experimental results show that all LEDs display the NC phenomenon.The voltage modulated electroluminescence(VMEL) experiment confirms that the reason of negative capacitance could be the strong recombination of the injected carries in the active region of luminescence.The measures also verify that the dependence of NC on voltage and frequency in different LEDs is similar:NC phenomenon is more obvious with higher voltage or lower frequency.