This observational, cross-sectional study aims to assess and characterize the clinical features associated with mixed features in bipolar depression, using DSM-5 criteria, Benazzi’s mixed depression (BMD), and Koukopoulos’ criteria (KMD). A minimum of 100 adult participants, diagnosed with bipolar depression (BD I, II, or other specified types), and meeting DSM-5 criteria for a current major depressive episode, will be recruited from outpatient and inpatient services of the Psychiatry Department at AIIMS, New Delhi. Convenience sampling will be used. Patients with psychiatric or neurological comorbidities, substance dependence (except nicotine), or uncooperative behavior will be excluded.Data will be collected through semi-structured interviews and standardized assessment tools, including BDRS, KMDRS, YMRS, HAM-A, CUDOS-M, CGI-BP, NIMH Life Chart, IGLSI, CSSRS, and SPAQ. The study will explore symptom profiles, associated clinical correlates, and the degree of overlap among diagnostic criteria using descriptive statistics, discriminant analysis, regression models, and Fleiss’ kappa for inter-criteria agreement. Ethical clearance will be obtained, and written informed consent will be required. The study aims to contribute to a better understanding of mixed features in bipolar depression within an Indian context, offering potential insights into diagnostic validity and improving clinical recognition of mixed states for appropriate intervention.