The RAS/ERK signaling pathway is a critical regulator of cellular processes such as proliferation, differentiation, and survival, core mechanisms that drive development. Dysregulation of RAS/ERK signaling is implicated in developmental disorders, including RASopathies, as well as in various cancers. Polo-like kinase 1 (PLK1) is a crucial orchestrator of both meiotic and mitotic cell cycle and plays an equally important role in development. Notably, abnormal ERK signaling can produce phenotypes that closely resemble those caused by PLK1 deficiency, suggesting a functional intersection between these pathways. In this review, we explore the emerging links between RAS/ERK and PLK1 signaling during development and highlight the broad range of biological processes potentially governed by their interaction.