Alfrink received his episcopal consecration on the following 17 July from Archbishop Paolo Giobbe, papal internuncio in The Hague, with Bishops Willem Lemmens and Jan Smit serving as co-consecrators, in Saint Catherine's Cathedral.

Alfrink succeeded Cardinal Johannes de Jong as Archbishop of Utrecht on 31 October 1955 and was named Apostolic vicar of the Catholic Military vicariate of the Netherlands on 16 April 1957.

He contributed to scientific publications, led the Pax Christi movement in the Netherlands, and was created Cardinal-Priest of San Gioacchino ai Prati di Castello by Pope John XXIII in the consistory of 28 March 1960.

During the last years of his life, Alfrink lived, with his housekeeper Dora, in a bungalow at Dijnselburg near Huis ter Heide.

[citation needed] Bernardus Johannes Cardinal Alfrink died in Nieuwegein at age 87, and after his funeral services in St. Catharine's Cathedral, was buried at St. Barbara's cemetery, next to his predecessor.

[citation needed] Alfrink refused to respond to the Dutch Reformed Church's call for clarification in regards to Princess Irene's conversion to Catholicism in connection with her intended marriage to Prince Carlos Hugo of Bourbon-Parma.