|Full name||Marco Osio|
|Date of birth||13 January 1966|
|Place of birth||Ancona, Italy|
|Height||1.80 m (5 ft 11 in)|
|Playing position||Manager (former midfielder)|
|2001–2002||Brescello (assistant coach)|
|2013||Bellaria Igea Marina|
|* Senior club appearances and goals counted for the domestic league only|
Osio started his playing career in the Torino youth system. In 1986, he moved at Empoli, and Parma in 1987. In his stay at Parma, he became one of the fan favourites, earning the nickname "Il Sindaco" (The Mayor) by the local supporters, and he was a key player for the team that climbed the Italian football divisions, up from Serie C1 to the top division, Serie A. During his time with the club, he enjoyed both domestic and European success, winning the Coppa Italia, and the European Cup Winners' Cup, also participating in the UEFA Cup. In 1993, after six seasons with Parma, he returned to Torino for two seasons before an unexpected move to Brazilian club Palmeiras, which makes him one of the very few Italian footballers to have ever played in the South-American country; he won the Paulista Championship with the club in 1996, despite having played only a handful of minutes for the club. After a few experiences at the Serie C level, he retired in 2001.
From December 2003 to February 2005 he served as head coach of Serie D side Valle d'Aosta and in the latter matchdays of the 2005–2006 season he coached Pergolese, another Serie D team. In 2006–07, Osio served as head coach of Crociati Parma (also known as Crociati Noceto), with whom he won Eccellenza and ensured promotion to the 2007–08 Serie D.  On July 2007, he was chosen by Serie C2 club Nuorese for their head coaching position. He was however sacked on 17 September due to poor results in the beginning of Nuorese's 2007–08 Serie C2 campaign (one point in three matches).
On 29 November 2011 he becomes the new coach of Ancona 1905 in Serie D, in place of the sacked Massimiliano Favo, until 3 February 2012 when he rescinds the contract by mutual agreement with the company.
- Paulista Championship: 1996
- "AMARCORD GRANATA: ROBERTO MUSSI E MARCO OSIO". Retrieved 23 January 2015.
- "A Noceto sognano un nuovo "sindaco": Marco Osio" (PDF) (in Italian). L'Informazione di Parma. Archived from the original (PDF) on 27 September 2007. Retrieved 30 July 2007.
- "Osio ha detto sì: Noceto abbraccia il "sindaco"" (PDF) (in Italian). L'Informazione di Parma. Archived from the original (PDF) on 27 September 2007. Retrieved 30 July 2007.
- "Osio: "Un premio al nostro lavoro"" (PDF) (in Italian). L'Informazione di Parma. Archived from the original (PDF) on 27 September 2007. Retrieved 30 July 2007.
- "MARCO OSIO E' IL NUOVO ALLENATORE DELLA NUORESE CALCIO" (in Italian). FC Nuorese Calcio. Archived from the original on 11 September 2007. Retrieved 30 July 2007.
- "UFFICIALE: Nuorese, esonerato Osio" (in Italian). TuttoMercatoWeb. 17 September 2007. Retrieved 17 September 2007.