  Topological exciton-polaritons are a burgeoning class of topological photonic
systems distinguished by their hybrid nature as part-light, part-matter
quasiparticles. Their further control over novel valley degree of freedom (DOF)
has offered considerable potential for developing active topological optical
devices towards information processing. However, the experimental demonstration
of propagating topological exciton-polaritons with valley DOF remains elusive
at room temperature. Here, employing a two-dimensional (2D) valley-Hall
perovskite lattice, we report the experimental observation of valley-polarized
topological exciton-polaritons and their valley-dependent propagations at room
temperature. The 2D valley-Hall perovskite lattice consists of two mutually
inverted honeycomb lattices with broken inversion symmetry. By measuring their
band structure with angle-resolved photoluminescence spectra, we experimentally
verify the existence of valley-polarized polaritonic topological kink states
with a large gap opening of ~ 9 meV in the bearded interface at room
temperature. Moreover, these valley-polarized states exhibit
counter-propagating behaviors under a resonant excitation at room temperature.
Our results not only expand the landscape of realizing topological
exciton-polaritons, but also pave the way for the development of topological
valleytronic devices employing exciton-polaritons with valley DOF at room
temperature
