The concurrence of the intracranial multiple primary tumors (MPTs) consisting of acoustic neuroma (AN) and pituitary adenoma is very rare. Here, we report a 42-year-old female who presented with left AN associated with pituitary adenoma. A total of three such cases have been reported before and which also presented with left AN with pituitary adenoma. Recently, a new "field cancerization" model has been proposed, which could explain MPTs and is consistent with the pathogenesis of such cases. The model also indicates that when a pituitary tumor or AN is detected separately, we might consider the development of "expanding field" after oncological treatment especially after radiotherapy in order to prevent the second field tumor occurring.