Working Mom is a drama is about a business woman turned housewife, Choi Ga Young. She used to be a successful business woman but that was until she got pregnant with her younger boyfriend's baby. Now she is married to Park Jae Sung and they have two sons together. In hopes of having her children well provided for, she tries to find somebody for her father so that he could remarry. The only trouble is her stepmother refuses to babysit her children while she goes back to work and to add onto her problems, her husband is secretly seeing his colleague.