We investigated an intracluster reaction induced by impact of (CS2)(n)(-) (n = 1-8) onto silicon and (La0.7Ce0.3)B-6 surfaces at collision energies of 100-2000 eV and 0-100 eV, respectively. Product anions scattered from the surfaces were mass analyzed by a tandem time-of-flight (TOF) mass spectrometer. In the impact onto the silicon surface, the intracluster reaction proceeds via (1) production of S- by dissociation of the core ion, CS2-, and (2) production of S-m(-) (m = 2,3) by abstractions of S from surrounding CS2 by S-m-1(-). In the impact onto a (La0.7Ce0.3)B-6 surface, essentially the same reaction mechanism operates except for the dimer reaction at collision energies less than 50 eV. The two isomers, CS2-(CS2) and C2S4-, give S-2(-), and the latter dissociates further into C2S2-. A similar reaction mechanism is found to operate in the intracluster reaction of (OCS)(n)(-).