The agger nasi cell is an important structure that affects frontal recess anatomy. The agger nasi cell is a part of the anterior ethmoid sinus and it can be seen on coronal CT scans of the sinus in views anterior to the middle turbinates. The case involves a fungus ball in the agger nasi cell, which is a rare occurrence. While the pathogenesis was unclear, a possible cause for the fungus ball may have been an issue with the drainage pathway due to middle meatal obstruction.