According to the invention, there is provided a novel soybean variety designated XB40X07. This invention thus relates to the seeds of soybean variety XB40X07, to the plants of soybean XB40X07 to plant parts of soybean variety XB40X07 and to methods for producing a soybean plant produced by crossing plants of the soybean variety XB40X07 with another soybean plant, using XB40X07 as either the male or the female parent.