Anderson-Fabry disease (AFD) is a multisystem X-linked lysosomal storage disorder caused by a deficiency in the enzyme α-galactosidase A (α-Gal A). This deficiency results in the intracellular accumulation of glycosphingolipids, primarily uncleaved globotriaosylceramide (Gb3) and its deacylated form, lyso-globotriaosylceramide (Lyso-Gb3), leading to progressive organ damage and functional impairment. The diagnostic evaluation for AFD involves clinical assessment and family history, supported by biochemical testing (α-Gal A enzyme activity and Lyso-Gb3 levels) and genetic analysis of the GLA gene. In cases of unexplained renal impairment or when genetic analysis is inconclusive, kidney biopsy is often required to confirm the diagnosis and guide targeted treatments. However, histological findings in kidney biopsies may sometimes be nonspecific, complicating the diagnostic process. This article aims to provide an updated perspective on the role of kidney biopsy in AFD, illustrating two cases that exemplify its pivotal role in confirming or excluding the suspected disease, proving to be both decisive and confounding in this complex clinical setting.