We determined the relative expression levels of the receptors , , , and and ligands , , , and with RNAseq analysis on fetal human inner ear samples, located TrkB and TrkC proteins, and quantified with in situ hybridization on histological sections between gestational weeks (GW) 9 to 19. Spiral ganglion neurons (SGNs) and satellite glia appear to be the main source of and synthesis peaks twice at GW10 and GW15-GW17. Tonotopical gradients of revert between GW8 and GW15 and follow a maturation and innervation density gradient in SGNs. follows the same time course of expression as . Immunostaining reveals that TrkB signaling may act mainly through satellite glia, Schwann cells, and supporting cells of Kölliker's organ, while TrkC signaling targets SGNs and pillar cells in humans. The expression is upregulated when is downregulated, suggesting a balancing effect for sustained TrkB activation during fetal development. The mission of neurotrophins expects nerve fiber guidance, innervation, maturation, and trophic effects. The data shall serve to provide a better understanding of neurotrophic regulation and action in human development and to assess the transferability of neurotrophic regenerative therapy from animal models.