A hydroponic lettuce culture solution includes ammonium and nitrate nitrogen. Percent of concentration of ammonium and concentration of nitrate nitrogen is between 1:4.9 and 1:5.4. A hydroponic lettuce cultivating system is further provided. The hydroponic lettuce cultivating system includes a cultivating tank and the hydroponic lettuce culture solution.一種水耕萵苣培養液,包括銨態氮及硝酸態氮,其中銨態氮的濃度與硝酸態氮的濃度比例為1:4.9至1:5.4之間。本發明更提供一種水耕萵苣栽培系統,包括一栽培槽以及上述的水耕萵苣培養液。