The bronchus intermedius is the continuation of the right main stem bronchus distal to the right upper lobe bifurcation, and courses in the same direction as the former, but with a slight rightward deviation.

It begins at the base of the right upper lobe bronchus and gives rise to the middle lobe and lower lobe bronchi.

Endoscopically the distal end of the bronchus intermedius has the appearance of a three-way junction with the medialis anterior and adjacent to the ventrobasalis, and finally the superior segmental bronchus (Nelson) posteriorly.

The bronchus intermedius is slightly flattened and measures 2.5 cm in length and 10 mm in diameter.