Born in Mexico City, he is the son of renowned actress and singer Verónica Castro and comedian Manuel "El Loco" Valdes. Castro also has a younger brother named Michelle Sáez Castro, his uncle is José Alberto Castro and his aunt is Beatriz Castro, who both are producers. As a baby, he made his acting debut with her during the telenovela named El Derecho de Nacer. Soon after, he appeared on a television commercial with her, and on the Mexican version of the broadway show Mame alongside the prominent actress Silvia Pinal.
Castro is one of the best selling Latin artists and has worked with renowned Latin producers including Kike Santander, Rudy Pérez, and Richard Daniel Roman.
In 1984, Castro made his first appearance on TV as a singer in the Televisa's child contest Juguemos a Cantar, but he did not qualify for the finals because of his young age.
Castro began his professional singing career in 1992 with the release of Agua Nueva. After appearing in several telenovelas and recording some albums as a teenager, Castro began his "internationalization" in 1993, starting with concerts in Puerto Rico. Castro dedicated a song to that country in his second album, Un Segundo En El Tiempo, titled "Puerto Rico" as a way of thanking the Puerto Rican public for supporting his career. He also modified his singing voice from the deep voice he employed in Agua Nueva to a softer one that he currently uses. His song, "Nunca Voy a Olvidarte" (I Will Never Forget You), became his first number-one hit at the Hot Latin Tracks charts in 1993 helped launched his career. Castro became an international teen idol and sex symbol almost instantly after he began touring, and he began what has been a fruitful international singing career and received a nomination for Pop New Artist of the Year at the Lo Nuestro Awards of 1993.
In 1994, Cristian released El Camino del Alma. The album hit, "Mañana", meaning Tomorrow, a song composed by Mexican singer, Juan Gabriel which was titled, "Mañana, Mañana". In 1995, he was part of the compilation album Boleros: Por Amor y Desamor written and produced by Jorge Avendaño Luhrs, recording "Vuélveme a Querer", which hit #2 on the Hot Latin Tracks (held off by Enrique Iglesias' debut single Si Tú Te Vas). In 1996, Cristian released El Deseo De Oir Tu Voz (The Wish To Hear Your Voice) which featured hits such as Morelia, Amor, Amarte a Ti, and the title track. At the 9th Lo Nuestro Awards, Castro received a nomination for Male Pop Artist of the Year.
Cristian has also done opening themes for telenovelas such as Morelia (1994) Angela (1998) and Mujer De Madera (Woman of Wood) (2004)
In 1997, Castro left Fonovisa and began contract to BMG with the release of Lo Mejor De Mi. Famous pianist Raúl di Blasio did the piano work for the song "Después De Tí...¿Qué?" (After You...What?). The album was nominated "Best Latin Pop Album of the Year". Following the album's success, Castro sang in duets with other singers such as Olga Tañón, Grupo Limite, and José Alfredo Jiménez. In 1999 he released Mi Vida Sin Tu Amor, which won him many credits because it had four singles to go in the Top ten of Billboard's Hot Latin tracks ("Alguna Vez" #2, "Por Amarte Asi" #3, Mi Vida Sin Tu Amor #3, Volver a Amar #4). In 2001, he released Azul, which won "Best Latin Pop Album of the Year". In 2005, he released Galltio Feliz, a collection of his childhood songs, Nunca Voy A Olvidarte...Los Exitos, a CD/DVD greatest hit album which features both Fonovisa and BMG songs,
In 2005, Castro released Días Felices with "Amor Eterno" and "Sin Tu Amor" as the album hit under the Universal Music Latino label. In 2006, Castro contributed on a tribute work to Victor Yturbe "El Piruli", in which he sang Mil Besos. On June 26, 2007, Castro released his first mariachi album, El Indomable, which was produced by Vicente Fernandez, and released the single from the album, "Tu Retirada". Castro announced that the divorce with Valeria has led him to bankruptcy. A new album, "El culpable soy yo", was released on April 28, 2009. He sang at the "Latin Grammy Celebra José José" ceremony and is said to have made one of the best tributes to his idol. On September 28, 2010, he released the single "La Nave del Olvido"and "Amor, Amor" as part of his tribute album to José José, Viva el Principe. In 2011, a follow-up to Viva el príncipe is being recorded under the title Mi Amigo El Príncipe.
After disappointing sales of albums with Universal Latin Entertainment, Castro returned to Sony Music. For his first album with Sony since Hoy Quiero Soñar, Castro recorded a live album titled Primera Fila which contains live recordings of his well-known songs as well as original songs. The album is set to be released in February 2013.
Besides of his solo career. Cristian Castro created the alternative rock-band La Esfinge.
Castro was married to the model Gabriela Bo from Paraguay. After he divorced Bo, he married his Argentinian Jewish ex-girlfriend, Valeria Liberman. Castro converted to Judaism upon marrying Liberman. He has since reverted to Roman Catholicism following his divorce with Liberman.
Studio albumsAgua Nueva (1992)
Un Segundo en el Tiempo (1993)
El Camino del Alma (1994)
El Deseo de Oír Tu Voz (1996)
Lo Mejor de Mí (1997)
Mi Vida Sin Tu Amor (1999)
Amar Es (2003)
Hoy Quiero Soñar (2004)
Días Felices (2005)
El Indomable (2007)
El Culpable Soy Yo (2009)
Viva el Principe (2010)
Mi Amigo El Príncipe (2011)
Compilation albumsExitos (1996)
Mis Mejores Momentos (1997)
Grandes Hits (2002)
Nunca Voy a Olvidarte...Los Exitos (2005)
Live albumsEn Primera Fila: Dia 1 (2013)
En Primera Fila: Dia 2 (2014)
El Cantar De La Muerte (2014)