Background: Nurses are particularly vulnerable to acquiring tuberculosis (TB) because they are in the frontline of patient care. There is inadequate implementation of cost-effective TB infection control (TBIC) measures in most health facilities. Training has been shown to be effective in improving the knowledge and work practices of nurses. This study sought to utilize a multi-method educational intervention to improve the TBIC-related knowledge and practices of nurses in two secondary health facilities in Ibadan, South-West Nigeria. Methods: This quasi-experimental study involved 200 nurses (100 each in the intervention and comparison groups). Baseline data were collected in May 2014. This was followed by training of the nurses in the intervention group. After 6 months, the second wave of data was collected and the nurses in the comparison group also received the training thereafter. The final wave of data collection took place 12 months after the commencement of the study. The mean scores of the nurses were determined and comparison was made between both groups at different time points using independent t-test. Results: The nurses in both groups were statistically comparable in their socio-demographic characteristics, and baseline mean knowledge (68.6 and 67.7%) and practice scores (79.1 and 80.6%) respectively. After the intervention group received the intervention, there were appreciable improvements in the scores at 6 months (knowledge - 85.9%, practice - 98.5%), which were significantly different from those of the comparison group (knowledge - 69.5%, practice - 78.8%). A large effect size was demonstrated in the improvement in knowledge score in the intervention group at 6 months compared with the other group (Cohen's d = 1.7). Similarly, there were improvements in the scores of the nurses in the comparison group at 12 months after the group had also received the intervention (knowledge - 88.2%, practice - 93.5%). At this point, the mean scores between both groups were no longer significantly different. Conclusions: The improvement in post-intervention scores implies that the educational intervention adopted for this study was effective in improving TBIC among the nurses. It also underscores the importance of continuous training/retraining of nurses and other healthcare workers in improving and sustaining TBIC at health facilities.