Mercury can be intercalated at room or moderate temperature into lamellar titanium and tantalum disulfides. The structure of intercalated compounds is described by two incommensurate sublattices corresponding to the disulfide host layers and the intercalated mercury,respectively. Depending on the synthetic procedure two different phases are obtained for mercury intercalated tantalum disulfide, which mainly differ in the relative orientation of disulfide and mercury networks. Mercury intercalation of 1T-TaS2 results in a tantalum coordination change from octahedral to trigonal prismatic. The mercury-to-host charge transfer is very low and more heavily involves the sulfur orbitals than previously observed for lithium intercalated compounds.