  Heavy fermion compounds exhibiting a ferromagnetic quantum critical point
have attracted considerable interest. Common to two known cases, i.e.,
CeRh$_6$Ge$_4$ and YbNi$_4$P$_2$, is that the 4f moments reside along chains
with a large inter-chain distance, exhibiting strong magnetic anisotropy that
was proposed to be vital for the ferromagnetic quantum criticality. Here we
report an angle-resolved photoemission study on CeRh6Ge4, where we observe
sharp momentum-dependent 4f bands and clear bending of the conduction bands
near the Fermi level, indicating considerable hybridization between conduction
and 4f electrons. The extracted hybridization strength is anisotropic in
momentum space and is obviously stronger along the Ce chain direction. The
hybridized 4f bands persist up to high temperatures, and the evolution of their
intensity shows clear band dependence. Our results provide spectroscopic
evidence for anisotropic hybridization between conduction and 4f electrons in
CeRh$_6$Ge$_4$, which could be important for understanding the electronic
origin of the ferromagnetic quantum criticality.
