Your Japanese institution applies for a Certificate of Eligibility (COE) first. Once received, you need: valid passport, COE original, visa application form, two passport photos, bank statements showing funds (¥120,000–¥150,000/month + tuition), financial guarantor documents (parents' income proof, bank statements, employment certificate), academic transcripts, and graduation certificates. Processing at Kathmandu embassy: 5–7 working days after COE. COE itself takes 1–3 months.