Summary: A novel waveguide power divider based on a coaxial-to-waveguide transition using a H-plane probe is presented. The waveguide consists of split metal blocks and substrates which are alternately stacked. The power divider is realized by arranging identical transitions using coaxial probes short-circuited with metal patterns on the substrate. The parasitic reactance of probes can be canceled out with the metal patterns on the substrate, so it is ease to design the power divider. The advantages of this structure are small footprint, low insertion loss, simple fabrication, and ease of design. A design method of the proposed power divider is described. The fabricated eight-way power divider shows excellent performances at 10 GHz-band.