Hamartomas are rare, tumour-forming, benign lesions that have been reported throughout the body that can resemble other malignant entities. Hamartoma subtypes can be distinguished based on their histological features. Sinonasal hamartomas may have presenting symptoms and radiological features that mimic other nasal neoplastic lesions. Therefore, it is essential to diagnose it accurately, as the treatment approaches can range from radical surgeries in malignant cases to a simple excision in hamartoma. In this paper, we report a novel case of sinonasal hamartoma, which demonstrates an unprecedented histological feature of glial tissue with astrocyte-like cells. Furthermore, we present the unconventional presenting symptoms and radiological features seen in this case that mimic the behaviours of nasal inverted papilloma (IP) lesions, thereby highlighting the need for careful investigation of such patients in order to distinguish both glial hamartoma and IP lesions. Concluding that identification of glial hamartoma as a new subtype of sinonasal hamartoma is crucial, as mistaking it for other lesions may subject patients to overly aggressive treatment and potential unnecessary harm.