The utility model discloses a corn precision planter capable of ridging, film mulching, watering and fertilizing. The corn precision planter comprises a frame, a water pump, a water box, a fertilizer box, a seed box, a ridger, a mould base, a compacting machine, a covering device, a fertilizer opener, a seed opener and a fine-seeding machine, wherein a one-way valve is arranged on the water pump; one end of a valve rod extends into the one-way valve; the other end of the valve rod is connected with one end of an adjusting screw; the other end of the adjusting screw is in contact with the middle of a connecting rod; the lower end of the connecting rod is hinged to the frame; the upper end of the connecting rod is in contact with blades of a ratchet wheel; block boards are mounted at the lower ends of the seed discharge groove and the drain tank of the seed opener; the two block boards are connected with each other through a torsional spring. The corn precision planter has the advantages that the requirements of fertilization, watering, film mulching, seeding and the like during operation are met by the corn precision planter, the depth of corn seeding is controlled by adjusting the position of a land wheel on the frame, and the seeding operation requirement of different row spacing can be met by changing the transmission ratio of a transmission.