To provide a plant-cultivating apparatus which can uniformly irradiate light on many plants in a simple structure.

This plant-cultivating apparatus 40 has cultivation units 30a to 30d arranged in a multistory structure, and the cultivation units have cultivation chambers 31a to 31d and light-focusing portions 21a to 21d, respectively. Light-guiding films 10p to 10s are arranged in the cultivation units, respectively. Light-introducing portions 11 are disposed at the longitudinal one ends of the light guide films, and light-outgoing portions 12a to 12c are disposed at the other end portions. Light radiated from a light source 20 is introduced from the light-introducing portions 11 into the light-guiding films and then emit from the light-outgoing portions to irradiate plants.