Sleep disturbances and depression are commonly experienced by postpartum women. We evaluated the preliminary efficacy of a modified version of cognitive-behavioral therapy for insomnia on mood, sleep, and fatigue in postpartum women with insomnia and depression in an open pilot study. Twelve postpartum women participated in five weekly individual treatment sessions. Statistically significant improvements were observed in sleep diary-rated sleep efficiency and total wake time, and subjective mood, insomnia severity, sleep quality, and fatigue. Further evaluation of the treatment using a controlled design is warranted.