PROBLEM TO BE SOLVED: To provide an endoscope processor and an endoscope system capable of automatically determining a projection direction when projecting a position of an endoscope on a plane with a simple configuration. SOLUTION: An endoscope processor 200 acquires first positions (P11, P12, P13) represented in three dimensions, and projects each first position on a plane, and first projection positions (Q11, Q12, Q13). ) Is acquired, the first evaluation value (L11 + L12) is calculated based on the first position set, and the second position is rotated around a predetermined axis for each first position (P11, P12, P13). The positions (P21, P22, P23) are calculated, the second position set including the second projected positions (Q21, Q22, Q23) obtained by projecting each second position on a plane is acquired, and the second position set is obtained based on the second position set. The evaluation value (L21 + L22) is calculated, and it is determined which position set to output the information based on each evaluation value. [Selection diagram] Fig. 3【課題】内視鏡の位置を平面に投影する際の投影方向を、簡素な構成で自動的に決定することができる、内視鏡プロセッサおよび内視鏡システムを提供する。【解決手段】内視鏡プロセッサ２００は、３次元で表される第１位置（Ｐ１１，Ｐ１２，Ｐ１３）を取得し、各第１位置を平面に投影した第１投影位置（Ｑ１１，Ｑ１２，Ｑ１３）を含む第１位置集合を取得し、第１位置集合に基づき第１評価値（Ｌ１１＋Ｌ１２）を算出し、各第１位置（Ｐ１１，Ｐ１２，Ｐ１３）について所定の軸の周りに回転した第２位置（Ｐ２１，Ｐ２２，Ｐ２３）を算出し、各第２位置を平面に投影した第２投影位置（Ｑ２１，Ｑ２２，Ｑ２３）を含む第２位置集合を取得し、第２位置集合に基づき第２評価値（Ｌ２１＋Ｌ２２）を算出し、各評価値に基づきいずれの位置集合に係る情報を出力するかを決定する。【選択図】図３
