Mariana Fernández de Córdoba y Ayala (c. 1394 – 1431) also known as Mariana de Ayala Córdoba y Toledo was the fourth Lady of Casarrubios del Monte in the province of Toledo. She was the daughter of Diego Fernández de Córdoba y Carrillo first Lord of Baena and Inés Ayala y Toledo third Lady of Casarrubios del Monte.