To provide a blood purification device capable of more accurately determining suitability of connection of a connection line.SOLUTION: A pressure applying step of applying a negative pressure or a positive pressure to one of the piping part or one of the flow paths of a blood circuit and a negative pressure or a positive pressure applied in the pressure applying step are connected through a communication line Propagating the negative pressure or positive pressure by the propagation process on the basis of the pressure detected by the pressure detection means, and judging whether the negative pressure or the positive pressure is propagated or not based on the pressure detected by the pressure detection means, And determining whether or not the connection of the communication line is appropriate based on the presence or absence of propagation of the communication line.(FIG.【課題】連結ラインの接続の適否をより精度よく判定することができる血液浄化装置を提供する。【解決手段】配管部又は血液回路の一方の流路に対して陰圧又は陽圧を付与させる圧力付与工程と、圧力付与工程で付与された陰圧又は陽圧を、連通ラインを介して配管部又は血液回路の他方の流路に伝播させる伝播工程と、圧力検出手段で検出される圧力に基づいて伝播工程による陰圧又は陽圧の伝播の有無を確認するとともに、当該陰圧又は陽圧の伝播の有無に基づいて連通ラインの接続の適否を判定する判定工程とを行わせ得る制御手段16を具備したものである。【選択図】図2
