We report the band structures of first stage potassium intercalated graphyne using the optimized geometries. The calculation was carried out using the full-potential linear-combination-of-atomic-orbitals method. The optimized distance between two graphyne layers sandwiching the intercalate layer is shorter than typical graphite intercalation compounds. These intercalation compounds are metallic. The character of the band around the Fermi level at Gamma point is C2p(z). The band with the character of K4s lies about 2.4 eV higher than the Fermi level at Gamma point for the compound intercalating one potassium in a unit cell, while that lies about 0.89 eV higher than the Fermi level at Gamma point for intercalating two potassium in a unit cell. Further we refer the amount of charge transfer between potassium and carbon atoms.