The object of the study was to investigate the effects of nitric oxide on the growth and glutathione dependent antioxidative system in cucumber (Cucumis sativus L. cv. Jinchun 2) seedlings. The results showed that exogenous nitric oxide increased the growth of cucumber seedlings in normal growth conditions. But exogenous methylene blue, the inhibitor of the key enzyme cGC during signal transfer of nitric oxide, markedly decreased the growth of cucumber seedlings. Exogenous nitric oxide alleviated the injured cucumber seedlings under NaCl stress. The activities of GR and DHAR, and the content of APX, GSH, ASA, GSH/GSSG was increased while the content of GSSG was decreased. The activity of MDAR was not affected under NaCl stress. But methylene blue blocked some effects of exogenous nitric oxide under NaCl stress, so the activity of GR and the content of GSH, ASA, GSH/GSSG was decreased. It was observed that the content of GSSG was increased, however, the activity of DHAR, MDAR and APX was not affected markedly under NaCl stress. Therefore nitric oxide was not adjusted the activity of GR, the content of GSH and ASA, GSH/GSSG through cGC. Nitric oxide couldn′t affect on the activity of MDAR. And there were some other ways which adjusted the activity of DHAR and the content of APX.