Strong preference is observed for the C-S bond scission process, leading to the formation of CH3++SH (CH3CH2++SH), in the collision induced dissociation (CID) reaction of CH3SH++Ar (CH3CH2SH++Ar). Since the dissociation-energy of 81.4 :kcal/mol (45.2 kcal/mol) for the CH3+-SH (CH3CH2+-SH) bond is significantly higher than that of 48 kcal/mol (33.9 kcal/mol) for the H-CH2SH+ [H-CH(CH3)SH+] bond, this observation indicates that the CID process is nonstatistical. The high yield for the C-S bond breakage process is attributed to the more efficient translational to vibrational energy transfer for the C-S stretching mode than for C-H and S-H stretching modes via collisional activation, and to weak couplings between the low frequency C-S and high frequency C-H and S-R stretching vibrational modes of CH3SH+ and CH3CH2SH+.