According to the invention, there is provided a novel soybean variety designated 91M10. This invention thus relates to the seed of soybean variety 91M10, to the plants of soybean 91M10, to plant parts of soybean variety 91M10 and to methods for producing a soybean plant produced by crossing plants of the soybean variety 91M10 with another soybean plant, using 91M10 as either the male of the female parent.