AbstractK6CrNb15O42crystallizes in the hexagonal system witha=9.126 (3) Å,c=12.068(3) Å,V=870.4(5) Å2, and space groupP62/mcm, Z=1. The structure was solved using direct method and Fourier Techniques. Of the 829 unique reflections measured by counter techniques, 448 with1≥ 3σ(I) were used in the least‐squares refinement of the model toR=0.034 (Rw=0.044). The structure of K6CrNb15O42may be described as consisting of corner‐shared and edge‐shared octahedra, the ring units composed of six octahedra of Nb(1) are corner‐shared one another along thec‐axis to form hexagonal column octahedra chains which are connected by K+and oct