An automatic harvesting device for a plant factory capable of stably producing crops throughout the year is provided. An automatic harvesting device of a plant factory includes a cultivation frame, a plurality of cultivation tanks, a track device, a plurality of cultivation plates, a mechanical arm system, and a nutrient solution replenishment system. The plurality of cultivation tanks 54 are arranged along the first direction X1 and are provided on the cultivation frame 52, and each cultivation tank 54 includes an injection head and a discharge head. The track device 56 is provided on the cultivation frame 52 and straddles a plurality of cultivation tanks 54. The plurality of cultivation plates 58 are provided in the track device 56 and are arranged along the second direction X2. The mechanical arm system 60 is provided on both sides of the track device 56 and takes out a plurality of cultivation plates 58 from the track device 56 or places the plurality of cultivation plates 58 on the track device 56. The nutrient solution replenishment system communicates with the injection heads and the discharge heads of the plurality of cultivation tanks 54 to supply the nutrient solution and adjust the concentration of the nutrient solution. [Selection] Figure 1【課題】通年で農作物を安定的に生産できる植物工場の自動収穫装置を提供する。【解決手段】植物工場の自動収穫装置５０は、栽培フレーム５２、複数の栽培水槽５４、軌道装置５６、複数の栽培板５８、機械アーム系６０、及び栄養溶液補充系を含む。複数の栽培水槽５４は第１の方向Ｘ１に沿って配列され、且つ栽培フレーム５２に設けられ、各栽培水槽５４は注入ヘッド及び排出ヘッドを含む。軌道装置５６は栽培フレーム５２に設けられ、且つ複数の栽培水槽５４に跨っている。複数の栽培板５８は、軌道装置５６に設けられ、且つ第２の方向Ｘ２に沿って配列されている。機械アーム系６０は、軌道装置５６の両側に設けられ、軌道装置５６から複数の栽培板５８を取り出し、或いは複数の栽培板５８を軌道装置５６に置く。栄養溶液補充系は、複数の栽培水槽５４の注入ヘッド及び排出ヘッドに連通し、栄養溶液を供給し、栄養溶液の濃度を調整する。【選択図】図１
