Purpose: The purposes of the study were to examine whether nurses' followership style influence organizational effectiveness and to test the model of organizational effectiveness including the factors of nursing organizational culture, leadership style, and followership style. Methods: Data were collected from July 10th to september 20th in 2006 from 451 nurses working in four acute care hospitals. Data analysis were performed by Chi-square test, ANOVA, Duncan test, Pearson Correlation, and maximum likelihood estimation, using the SAS and LISREL 8.30 program. Results: The findings showed that the types of nurses' followership were classified as passive (21.1%), alienated (8.2%), conformist (16.4%), pragmatist (35.9%), and effective style (18.4%). There was significant difference in the organizational effectiveness among the nurses with different followership styles. In testing the path model, transformational, transactional leadership directly influenced followership style. Followership directly influenced organizational effectiveness. Conclusion: The overall fitness of the model was good, evidenced by general fitness index (GFI)=.94, adjusted goodness of fitness index (AGFI)=.82, and root mean square residual (RMSEA)=.06. Based on the findings, it is recommended to develop a program for enhancing effective followership in nursing organization.