This study examined the characteristics of service users requiring frequent visits (≥ 3 times/week) and support coordination from home-visit nursing stations and psychiatric home-visit nursing in Japan. Psychiatric home-visit nursing is vital for individuals with mental disorders, but its implementation has lagged behind physical home-visit nursing because of Japan's historical emphasis on institutional psychiatric care. A questionnaire survey was conducted from October 2024 to January 2025, involving 56 home-visit nursing stations with 224 service users. Home-visit nursing stations into four types and users into three care patterns: persistent frequent visits without support coordination, support coordination without persistent frequent visits, and both. In total, 15.6% of users received home visits ≥ 3 times/week, with significant variation by facility type. Frequent visits were associated with schizophrenia, long-term service use, comorbid physical conditions, and low levels of functioning (Global Assessment of Functioning [GAF], mean score, 41.9). Those needing frequent visits and coordination had the lowest GAF scores and highest rates of hallucinations, impulsivity, and self-harm. The primary reasons for support coordination and frequent visits included psychiatric symptom fluctuations, changes in self-care, and family-related issues. The finding show that frequent psychiatric home-visit nursing is associated with diverse and complex care needs requiring tailored coordination and resource allocation, highlighting the importance of structured, individualized care planning and the need to document visit rationales and assessment methods. This is the first Japanese study detailing the profiles of high-need psychiatric home-visit nursing users, offering foundational data for future policy and practice development.