Background. Mentors in healthcare professions have a major impact on quality nursing education during clinical practice, and mentorship training is one means of improving mentors’ understanding high-quality education.

Method. This was a quasi-experimental study involving non-randomized, pre- and postintervention measurements. Training comprised a blended method for the intervention group (n = 192) and an online-only method for the control group (n = 64) in two Finnish hospital districts.

Results. Mentors’ competence improved after training, and all but one area of mentorship competence (reflection during mentoring) showed a statistically significant difference. The blended training produced larger mean differences than the online-only training in the competence areas requiring mentor-student interaction.

Conclusion. Both training methods increased mentorship competence . Healthcare organizations must seriously consider implementing mentorship competence training using methods that are effective and facilitate more efficient allocation of limited available resources.