Inbred broccoli lines, designated BRM50-3906 are disclosed. The invention relates to the seeds of inbred broccoli lines BRM50-3906, to the plants of inbred broccoli lines BRM50-3906, and to methods for producing a broccoli plant produced by crossing the inbred line BRM50-3906 with itself or another broccoli line. The invention further relates to hybrid broccoli seeds and plants produced by crossing the inbred line BRM50-3906 with another broccoli line.