环庚烷（化学式：C₇H₁₄），又名软木烷，是七个碳的环烷烃。

一般情况下为无色油状液体，不溶于水，但可以与醇、醚、苯等有机溶剂混溶。易燃，其蒸气可以与空气形成爆炸性混合物，遇热源和明火有爆炸和燃烧的危险。

环庚烷蒸汽对眼部、皮肤有刺激性，大量吸入时有麻醉作用。

理论计算显示环庚烷共有四个较为稳定的构象：椅型、船型、扭椅型和扭船型（图）， 其中以扭椅型最为稳定。 环庚烷的衍生物主要采取扭椅型构象。 各个扭椅型结构可通过假旋转作用迅速互相转化。

Cycloheptane is a cycloalkane with the molecular formula C₇H₁₄. Cycloheptane is used as a nonpolar solvent for the chemical industry and as an intermediate in the manufacture of chemicals and pharmaceutical drugs. It may be derived by Clemmensen reduction from cycloheptanone. Cycloheptane vapour is irritating to the eyes and may cause respiratory depression if inhaled in large quantity.