|Date of birth||17 September 1963|
|Place of birth||Latina, Italy|
|Height||1.78 m (5 ft 10 in)|
|Playing position||Manager (former defender)|
|* Senior club appearances and goals counted for the domestic league only
Somma started his coaching career in 1997 with amateur team Pro Cisterna, and then served as head coach for several other Serie D teams, including Potenza and Cavese, winning promotion to Serie C2 with the latter. In 2003, he was appointed at the helm of Serie C1 team Arezzo, leading the Tuscan side to a historical triumph in the league. This caused interest by Empoli, which chose to offer him the job for their 2004–05 Serie B campaign. As Somma managed to win a personal third consecutive promotion, leading Empoli to become Serie B runners-up, he was confirmed by the Tuscans for their 2005–06 campaign; despite an impressive start, Empoli's performances slowly fell down, causing Somma to be dismissed from his job on January 2006.
Somma started the 2006–07 season as head coach of Brescia in the Serie B, with the aim to lead the rondinelle back to the top flight: however he was sacked on February 2007 as he did not manage to obtain more than a mid-table place. On October 2007 he was appointed at the helm of Piacenza to replace Gian Marco Remondina. He led the biancorossi to escape relegation in the season, but was sacked immediately after the final matchday.
On October 2009 he returned into football management as new head coach of Triestina, replacing dismissed boss Luca Gotti. However, he was sacked on February 2010, with Triestina in 18th place, and only one point shy of immediate relegation.
On 8 June 2014 he was named new head coach of Lega Pro club Salernitana. He was however dismissed as head coach only two months later, on 17 August 2014, after only one game in charge of the team (a 0–1 loss to Alessandria in the first round of the 2014–15 Coppa Italia).
- "Mario Somma". FootballPlus. Retrieved 2007-12-04.
- "Mario SOMMA" (in Italian). La Gazzetta dello Sport. Retrieved 2007-12-04.
- "Via Remondina, ecco Somma" (in Italian). SKY Life. 2007-10-23. Archived from the original on 2007-10-24. Retrieved 2007-12-04.
- "Comunicato Stampa" (in Italian). Piacenza Calcio. 2008-06-01. Archived from the original on 2008-06-09. Retrieved 2008-06-01.
- "MARIO SOMMA E' L'ALLENATORE DEL MANTOVA" (in Italian). AC Mantova. 2009-02-09. Archived from the original on July 22, 2011. Retrieved 2009-02-09.
- "Sollevato dall'incarico mister Luca Gotti. La conduzione tecnica della Prima Squadra verrà affidata al tecnico Mario Somma" (in Italian). US Triestina Calcio. 2009-10-06. Archived from the original on 2011-09-27. Retrieved 2009-10-09.
- "Mario Somma sollevato dall'incarico di allenatore della Prima Squadra" (in Italian). US Triestina Calcio. 2010-02-09. Archived from the original on 2011-09-20. Retrieved 2010-02-09.
- http://www.tuttosport.com/calcio/serie_b/grosseto/2012/10/01-216026/Grosseto,+via+Moriero%3A+Somma+%26%23232%3B+il+nuovo+tecnico. Retrieved 2013-02-11. Missing or empty
- "Salernitana, Somma è il nuovo allenatore: «Sono commosso, tifo per questa squadra»" (in Italian). Corriere del Mezzogiorno. 8 June 2014. Retrieved 18 August 2014.
- "Salernitana, via Somma: Lotito lo caccia prima dell'inizio e chiama Menichini" (in Italian). La Gazzetta dello Sport. 18 August 2014. Retrieved 18 August 2014.