Giacomo Guido Ottonello (born 29 August 1946) is an Italian prelate of the Catholic Church who has spent his career in the diplomatic service of the Holy See.

Giacomo Guido Ottonello was born in Masone, in the Province of Genoa, on 29 August 1946.

[1] On 25 March 1980 he entered the diplomatic service of the Holy See, working in Pakistan, El Salvador, Lebanon, France, Spain and Poland.

[1] On 29 November 1999, Pope John Paul II appointed him apostolic nuncio to Panama and titular archbishop of Sasabe.

[4] On 26 February 2005, John Paul named him Nuncio to Ecuador,[5] where for over twelve years he attempted dialogue and mediation with the anticlerical President Rafael Correa,[6] On 1 April 2017, Pope Francis appointed him apostolic nuncio to Slovakia.