In order to explore the ameliorating role of nitroprusside (SNP) on inhibition of seed germination caused by cadmium, the effects of 10, 30, 50, 100, 200 and 500 μmol/L SNP on seed germination, seedling growth and physiological characteristics of rice were studied under cadmium stress. The results showed that the rice seed germination and seedling growth were significantly inhibited, the germination potential, germination index, vigor index, root and shoot length, and the activities of SOD, GPOD, APX and CAT significantly increased and the malondialdehyde (MDA) content significantly decreased under 100 μmol/L cadmium stress compared to the control. Low concentration of SNP (≤100 μmol/L) could alleviate the inhibition effects of cadmium, under which the germination index, vigor index, root length, shoot length, root and shoot fresh weight, the activities of SOD, GPOD and APX of rice seedlings increased and the MDA content was significantly inhibited. Thirty μmol/L SNP exhibited the most prominent alleviating effect, but the effect faded away with the increase of SNP concentration. When the concentration of SNP reached 500 μmol/L, the toxicity effect of cadmium stress on the rice seedlings was aggravated.