Abstract: Objective: To investigate the correlation and dynamic change of activities of daily living and nurses workload with four different single diseases. Methods: A total of 217 inpatients with four different diseases were selected from a local tertiary grade A hospital. The direct nursing hours and Barthel index were recorded. Results: We found negative correlation between the activities of daily living and nurses workload in four different diseases. For nursing workload, the highest is colorectal cancer, followed by gastric cancer, gallbladder stones, and breast lumps. To analyzing nursing workload of the patients with the different stages of hospitalization, it showed that the nursing workload on operation day are significantly higher than other times, nursing care workload is similar on operation day and postoperation second day, nursing working hours is decreasing with the increase of hospitalized days, and all diseases present similar trends. Conclusion: The ability of performing activities of daily living is a significant factor influencing nursing workload, which should be taken into consideration in nursing staffing.