Provided is a plasma etching method of etching OCOC film in which HTO films and carbon films are alternately laminated by plasma of mixed gas containing first CF-based gas or second CF-based gas and oxygen gas using a silicon film formed on OCOC film as a mask. The etching of OCOC film includes a first etching process of etching a region spanning from the top surface to the middle of OCOC film by plasma of mixed gas containing first CF-based gas having a predetermined ratio of content of carbon to content of fluorine and oxygen gas and a second etching process of etching a region spanning from the middle of OCOC film to the lowest layer by plasma of mixed gas containing second CF-based gas having a ratio of content of carbon to content of fluorine, which is higher than the predetermined ratio of first CF-based gas, and oxygen gas.