This paper reports a 32-year-old male patient with type 1 diabetes mellitus who was admitted to the hospital due to "redness and swelling of the right eye after being struck by a bamboo stick, accompanied by vision loss for one month and worsening over the past two days". The patient was initially treated for bacterial endophthalmitis, but symptoms recurred and progressively worsened. Rapid diagnosis of fungal endophthalmitis caused by Purpureocillium lilacinum was achieved via metagenomic next-generation sequencing (mNGS) of intraocular fluid, and the diagnosis was corroborated by conventional culture results. Subsequently, the patient underwent surgical intervention and received systemic and topical voriconazole therapy. The symptoms and signs significantly improved, and vision was improved.