A novel soybean cultivar, designated SO22220, is disclosed. The invention relates to the seeds of soybean cultivar SO22220, to the plants of soybean SO22220 and to methods for producing a soybean plant produced by crossing the cultivar SO22220 with itself or another soybean variety. The invention further relates to hybrid soybean seeds and plants produced by crossing the cultivar SO22220 with another soybean cultivar.