Background: Digital transformation in healthcare has demanded complete and accurate nursing documentation through Electronic Medical Records (EMRs). However, EMR completeness has remained suboptimal, indicating that technological implementation alone is insufficient. Organizational factors, particularly transformational leadership and organizational culture, play a critical role in influencing nurses’ documentation practices. Effective leadership may enhance supervision and engagement, while a supportive culture promotes collaboration and accountability. Nevertheless, evidence regarding their combined influence on EMR completeness remains limited. Purpose: This study aimed to analyze the relationship between transformational leadership style and organizational culture on the completeness of EMRs among nurses. Methods: A mixed-methods research design was employed. Quantitative data were collected from 112 nurses to examine the relationship between transformational leadership, organizational culture and the completeness of electronic medical records, while qualitative data were obtained from eight key informants to identify the contextual factors influencing documentation practices. Results: The findings revealed that the majority of EMR documentation was incomplete (60.7%). A statistically significant but negative correlation was identified between transformational leadership and documentation completeness (p = 0.002; r = -0.287), Qualitative findings highlighted systemic barriers, including high workload, limited system usability, and technical constraints. A perception gap was also identified between nurses and management. Conclusion: Improving EMR documentation completeness required an integrated approach involving leadership effectiveness, organizational culture, system usability, and workload management.