The invention discloses a production method of a polylactic acid carpet. The method comprises the following steps of S1, preparation of a polylactic acid fiber, wherein after corn-husk crops are ground, starch is extracted from the crops and then prepared into non-refined glucose, the glucose is fermented into lactic acid, the lactic acid is concentrated into lactide, a lactide monomer is subjected to vacuum purification and then subjected to loop opening operation, so that the monomer is polymerized into polylactic acid, by adopting the polylactic acid with molecular weight of 330,000, firstly, vacuum drying is conducted, then melting spinning is conducted, and a polylactic acid fiber can be obtained; S2, preparation of a carpet base fabric, wherein spun yarn formed by the polylactic acidfiber is put into a stranding machine for stranding and sizing, the polylactic acid spun yarn after stranding and sizing is put on a tufting weaving machine for weaving, and finally the polylactic acid carpet base fabric is formed; S3, printing; S4, color fixation and drying; S5, washing with water and reduction; S6, winding of a finished product. The production method is simple, the material isdegradable, and a rebound effect is good.