Abstract: Effects of different nitrogen forms on the growth and quality of the three potherbs including Gynuradivaricata (L.) DC., Talinum paniculatum (Jacq.) Gaert. and Gynurabicolor(ROXB.)DC was studied under solution culture with optimal nitrogen concentration (12 mmol/L). The main results are as follows: ①The fresh weight of shoot of the three potherbs increases gradually with the decrease of the ratio of NH4+∶NO3－ under the condition of optimal nitrogen concentration. When the ratio of NH4+∶NO3－is 25∶75, the maximum fresh weight is obtained for Gynuradivaricata and Talinum paniculatum, and the maximum fresh weight is obtained for Gynurabicolor when the ratio of NH4+∶NO3－ is 0∶100. The maximum dry weight is obtained for Talinum paniculatum and Gynurabicolor when the the ratio of NH4+∶NO3－ratio is 25∶75, and the maximum dry weight is obtained for Gynuradivaricata when ratio of NH4+∶NO3－is 0∶100. ②The contents of nitrate and nitrite of the three potherbs increase dramatically and the total amount of free amino acids decreases with the decrease of the ratio of NH4+∶NO3－. As a result, appropriate increase of ammonium application would benefit the decrease of the content of nitrate in potherbs. ③The content of V–C, soluble sugar and soluble protein are in high level when the the ratio of NH4+∶NO3－is 75∶25 or 50∶50.