Clinical mentoring is work-based training for the capacity building of health care workers. This study determined if there were benefits and increases in knowledge levels for 33 selected health workers across 5 health facilities in Jigawa State following the introduction of clinical mentoring. Questionnaires were used to determine biodata and knowledge scores of mentored health workers and also key departmental activities before and after a 6 months period of introduction of clinical mentoring. Data was analyzed with SPSS version 20. Over 90% of the 33 mentored health workers showed an increase in their knowledge scores. The mean percentage score of the health workers increased significantly from 56.3 ± 2.1 before the start of clinical mentoring to 74.7 ± 1.7 (p < 0.001) six months later. Mortality review meetings were also introduced. This study has shown that clinical mentoring is beneficial for improving the clinical knowledge of mentored health workers.