As an active participant of the Second Vatican Council and a consultor of the Commission for the Revision of the Canon Code, Bishop Professor Walenty Wójcik greatly contributed to canonist science by writing commentaries, reviews and reports related to the subject of the Council. By writing reports on the Council, Wójcik made the content of the conciliar deliberations more accessible to the general public. Among the many topics that he raised, he analysed the issue of unduly long sessions of the Council, suggesting changes to the procedure. Importantly, he co-authored many proposals for revised canon law and submitted them for the Polish Episcopal Conference. He believed that the revision work must be founded on the new ideas of Vatican II. The presented article is an overview of his work related to the Council and the reform of canon law that took place as a result of it.