The use of electroconvulsive therapy (ECT) during twin pregnancy has been insufficiently studied, and there is limited evidence regarding its safety. Here, we present a case of successful use of ECT for severe major depressive disorder during twin pregnancy. The patient suffers from psychotic depression with catatonic presentation and Cotard syndrome (delusions with denial of internal organs). This case illustrates the difficulty in managing severe antenatal depression and addresses the guidelines for the ECT protocol (anaesthetic modalities, obstetrical monitoring, and duration of treatment) during twin pregnancy.