The mass spectra of a series of tris(N,N-dialkyldithiocarbamato)metal complexes of chromium, iron, cobalt, ruthenium, rhodium and thallium have been investigated. The fragmentation patterns of these and related compounds are discussed. The major decomposition pathways involve loss of the dithiocarbamate ligand radical and loss of S, S2 and SCNR2 groups from tris- and bis(dithiocarbamato)metal complex ions. The parent molecular ions are present in the mass spectra of most of these complexes but with relative abundances which vary greatly. In complexes of the type LFe(S2CNR2)2 where L = Cl or S2C2(CF3)2, neutral dithiolene and chlorine atom elimination are the major decomposition reactions under electron impact. The parent molecular ions for these complexes are virtually absent and dithiocarbamate ligand radical loss from the parent molecular ion is not observed.