I describe two new species of squeaker frog (Arthroleptidae: Arthroleptis) from the Eastern Arc Mountains of Tanzania. These new species are distinguished from other miniature Arthroleptis in the Eastern Arc Mountains by the combination of very small adult body size (< 15 mm snout–vent length), a pronounced dark inguinal spot, and color patterns unique to each species. The new species could be the smallest frog species known from East Africa and among the smallest species of Arthroleptis. An estimate of phylogeny on the basis of mitochondrial DNA sequences reveals that these morphologically cryptic species are sister taxa that compose a basal lineage within a clade of miniature Arthroleptis. Their description hints at a diverse cryptic amphibian fauna in the Eastern Arc Mountains that awaits additional discovery through molecular methods.