Abstract: The molecular and crystal structure of the new compound [Co(H_2O)_4(NCS)_2]_2. (18-Crown-6) has been reported in a preiours paper by one of us. The electronic structure of the same compound has been calculated using CNDO/2 method, and the results are reported in this paper. Some interesting results have been obtained. Calculated atomic net charge, Mulliken bond order, total and local density of states (TDOS and LDOS) for isolated and interacted systems have been given. It is shown that a coordinate unit is bonded to a 18-crown-6 molecule by four hydrogen bonds which have different strengthes. These results are in agreement with the experimental measurements. It is concluded that the hydrogen bond interaction in the coordinated units is of primary importance for the explanation of the stability of this coordination compound.