Provided is a hydroponic cultivation method that does not use chemical fertilizers or chemically-synthesized agrochemicals or can reduce their use amounts. The present invention provides a hydroponic cultivation method that uses beneficial micro-organisms such as a mycorrhizal fungus and its partner bacteria. By allowing a partner plant to grow between rows of a crop, said partner plant enabling easy growth of the mycorrhizal fungus and its partner bacteria, or by using a hydroponic cultivation apparatus that can create an environment under which these beneficial micro-organisms are easy to grow, the crop can be increased in yield and quality, and chemical fertilizers or chemically-synthesized agrochemicals can be used in smaller amounts or can no longer be needed.
