In this paper, we have sought correlations between the null fraction and luminosity and spindown energy loss rate of pulsar for total sample of 110 radio pulsars. Our methods are comparison method and analysis of correlation technique. Our results are that the correlation coe±cient and significance of the correlation between the null fraction and luminosity are r = ¡0:413 and P = 0:000 < 0:05, respectively. And this suggests that there is a significant anti-correlation between the null fraction and luminosity. The correlation coefficient and significance of the correlation between the null fraction and spindown energy loss rate are r = -0.373 and P = 0.000 < 0.05, respectively. And this suggests that there is a signi¯cant anti-correlation between the null fraction and spindown energy loss rate. The conclusion of the study is that the luminosity of nulling pulsar decreases with increasing of null fraction, the null fraction of nulling pulsar increases with decreasing of spindown energy loss rate.