The Japanese guidelines for psoriasis therapy with cyclosporin microemulsion preconcentrate (CyA MEPC) has been revised, and the clinical application of CyA MEPC is being expanded to include mild to moderate psoriasis. In this study, we aimed to confirm the clinical efficiency of low-dose cyclosporin therapy in patients with moderate psoriasis vulgaris. After informed consent was obtained, 19 patients with psoriasis vulgaris were enrolled in this study. Each patient basically administrated CyA MEPC, 2.5 mg/kg/day, orally over 12 weeks. When the psoriasis area and severity index (PASI) score showed a 75% reduction from the initial value, the dosage of CyA MEPC was reduced to 1.5 mg/kg/day and added a topical application of active vitamin D3 ointment. We interviewed the patients as to their satisfaction for the usefulness and cost of the treatment. All patients obtained improvement within 12 weeks. In 10 patients whose PASI score reduced over 75%, we could reduce CyA MEPC dosage. No adverse effects were noted in any patients during the treatment. It is of note that the cost for 1.5 mg/kg/day administration of CyA MEPC was accepted by all the patients. In conclusion, this preliminary study suggests that the CyA MEPC is effective, safe and would provide patients with acceptable costs.