The invention provides a full-
biodegradable plastic mulching film, a preparation method and application thereof. The full-
biodegradable plastic mulching film comprises the following components in parts by weight: 100 parts of a full-biodegradable resin, 10-30 parts of an auxiliary agent, 10-60 parts of
modified starch and 10-100 parts of modified
calcium carbonate, wherein the full-biodegradable resin is prepared from one or more of poly (butylene succinate) (PBS),
polylactic acid (PLA), polyhydroxyalkanoate (PHA), poly (butylene
adipate-butylene terephthalate) (PBAT) and
polypropylene carbonate (PPC). According to the biodegradable mulching film, the contradiction that crops need longer service life of the mulching film and lower thickness of the mulching film and the requirement on the lowest thickness of a
polyethylene plastic mulching film can be solved, and the technical scheme of the biodegradable mulching film also has the effects of slow degradation in the early stage, strong protection capability and accelerated degradation in the later stage, so that the influence of the biodegradable mulching film on the planting of succeeding crops is reduced.