Taking lettuce as material，with the method of randomized block design，the influence of micro-nano water on the seed germination rate，plant height，spreading width and root growth of lettuce were studied.The results showed that soaked in nano water，the seeds could get a higher germination percentage and could grow into stronger seedlings.With the usage of nano water in shallow liquid flow cultivation of lettuces，the quality of seedlings were improved，the growth of roots were promoted and the yields increased.Using nano water in the substrate cultivation of lettuces，the height，spreading width，yield and roots of lettuce were promoted.The experiments proved that the nano water with oxygen bubbles could promote the growth of lettuces most obviously，likewise，nano water with air bubbles could also showed obvious effect on promoting the yield and growth of roots.