Joseph Muzquiz (boen José Luis Múzquiz y de Miguel; 1912-1983) was a Spanish Catholic priest who was an early member of Opus Dei.

He went to Madrid to study engineering, and it was there that he met Josemaría Escrivá, the future founder of the Opus Dei movement.

He returned to the United States in 1976, settling at Arnold Hall Conference Center, an Opus Dei apostolate based in Pembroke, Massachusetts.

On 20 June 1983, he suffered a heart attack while teaching a class there, and died the following day at Jordan Hospital in Plymouth.

The cause for his canonization was opened on 2 June 2011, under the authority of the Archbishop of Boston, Cardinal Seán Patrick O'Malley, in whose jurisdiction Muzquiz died.