José Luis Mumbiela Sierra (born 27 May 1969 in Monzón, Spain) is a Spanish-born Roman Catholic clergyman and Bishop of the Holy Trinity Diocese in Almaty.
He was ordained on 25 June 1995 and was incardinated in the diocese of Lleida.
In 1998 began missionary work in Kazakhstan.
He was rector of the seminary in Karaganda.
On 5 March 2011 Pope Benedict XVI appointed him bishop of the Holy Trinity in Almaty.
He replaced the retiring Bishop Henry Howanca, OFM.
On 8 May 2011 Sierra was ordained bishop by Apostolic Nuncio to Kazakhstan, Archbishop Miguel Maury Buendía.