Spanish minister and politician. One of the three sons of Blas López Pelegrín and Eugenia Martínez Selas he was born in Molina de Aragón, together with his brothers Tomás and Juan. In 1815, he had to ask for a permission to marry Juana Rejón de Silva.

He received his bachelor's degree in Philosophy and Theology by the University of Zaragoza, and years later he received his PhD in Canon law. On 3 May 1804 he was appointed judge of the Royal Chancery of Valladolid.

During the French invasion, he took part of the Junta General of Armamento and Defensa of Castilla la Vieja, of which he was named president (15t November 1808). In 1810, being member of the Junta Suprema de Represalias, he was elected to the Cortes as Vice President and then President of the Junta Suprema de Censura. Apart from these charges he was appointed prosecutor of the Provisional Chamber of Justice of the Treasury and later of the Supreme Court of Justice.

After King Ferdinand VII return to the absolutist regime with the Councils structure, López Pelegrín was appointed attorney of the Council of Castilla (12 June 1814). A year later, he became Minister of the same Council. During the first crisis of the government of the Trienio Liberal (Liberal Triennium) he entrusted Eusebio Bardají the creation of a new cabinet, in which Pelegrín held the post of Governor of Overseas Territories (from 3 June 1821 to 28 February 1822).

After the creation of the Royal Council of Spain and the Indies, he was appointed chairman of the Justice Section, in which he worked until its dissolution (30 September 1836) as a consequence of the proclamation of the Constitution of 1812.