A light-emitting device comprising a pair of electrodes and one or more organic layers disposed between the electrodes, the one or more organic layers comprising a light-emitting layer. At least one of the organic layers comprises a transition metal complex containing a moiety represented by the following formula (1): ##STR00001## wherein M.sup.11 represents a transition metal ion; and R.sup.11, R.sup.12, R.sup.13, R.sup.14, R.sup.15, R.sup.16 and R.sup.17 represent a substituent or a single bond, respectively, or a tautomer thereof.