Shotgun metagenomics (SMg) usefulness for brain abscess diagnosis is not known. We describe a case of brain abscess diagnosed with SMg and provide a review of the literature. A 70-year-old woman was diagnosed with multiple brain abscesses. Standard culture techniques and 16S rRNA gene sequencing of abscess samples remained negative. SMg finally revealed the presence of sequences from Streptococcus anginosus and Fusobacterium nucleatum, leading to antimicrobial treatment adaptation and corticosteroids initiation. The patient finally recovered. A literature review retrieved fifteen other cases of brain abscesses diagnosed with SMg. SMg results led to changes in patient management in most cases. The existing literature about the performances of SMg, its advantages, future evolutions, and limitations is then discussed. SMg place in routine should be evaluated and defined through prospective studies.