The present invention addresses the problem of providing: a plastic cell having a sealing portion that maintains the ability to remain sealed even when a plastic substrate deforms into any shape having irregularities and curved surfaces; and a method for manufacturing the plastic cell. The plastic cell according to the present invention has a first plastic substrate, a first transparent conductivelayer, a fluid layer, a second transparent conductive layer, and a second plastic substrate in this order. Additionally, the plastic cell has a sealing portion in which a portion of the first plasticsubstrate or the second plastic substrate is deformed so as to seal the fluid layer. The sealing portion includes a corrugated region that satisfies the following expression (1): P <= 40A (1) Where Prepresents the corrugation pitch, and A represents the corrugation amplitude.