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Reaction of the thiol‐terminated fourth‐generation dendrimer 2‐G4(96 SH groups) with the gold cluster compound Au55(PPh3)12Cl6in a 3:1 molar ratio in dichloromethane results in the formation of bare Au55clusters. The cuboctahedrally shaped Au55particles coalesce to well‐formed microcrystals (Au55)∞. The role of the dendrimer is not only to remove the phosphine and chlorine ligands but also to act as an ideal matrix for perfect crystal growth. Transmission electron microscopy (TEM), small‐ and wide‐angle X‐ray diffraction (SAXRD and WAXRD) measurements indicate a structure where rows of edge‐linked Au55building blocks form a distorted cubic lattice. The X‐ray data fit best if a 5 % reduction of the Au−Au bond length in the Au55clusters is assumed, in agreement with previous extended X‐ray absorption fine structure (EXAFS) measurements. Energy‐dispersive X‐ray spectroscopy (EDX) analyses and IR investigations show the absence of PPh3and Cl in the microcrystals.