1994–2006: Early career Lettieri was the assistant coach of
1860 Munich from July 1994 to April 1997. He then became manager of
Bayern Hof from 23 April 1997 to 30 June 2000. In the 1996–97 season, under Lettieri, Bayern Hof got two wins, one draw, and three losses to finish 15th in the Bayernliga. They finished in 10th place in the 1997–98 season, 14th in the 1998–99 season, and in fourth place in the 1999–2000 season. Then on 1 July 2000, Lettieri became manager of
FC Augsburg In the
Bayernliga, Augsburg finished fourth in the 2000–01 season and first in the 2001–02 season. On 20 June 2002,
Bonner SC announced Lettieri as their new manager. He started on 1 July 2002. He was in Bonn until 11 September 2003 when he joined then Bayernliga side
SpVgg Bayreuth. His last match as Bonn's manager was a 2–0 loss to GFC Düren on 7 September 2003. He was in sixth place when he left Bonn. While at Bayreuth, during the 2003–04 season, he finished with a record of 11 wins, eight draws, and six losses to finish seventh in the Oberliga Bayern table. Bayreuth won promotion to the
Regionalliga Süd during the 2004–05 season. They finished 10th in the
2005–06 season.
2006–10: Darmstadt, Wacker Burghausen, and Weiden On 10 June 2006, Lettieri signed a two–year contract with
Darmstadt 98. During his time at Darmstadt, he lost 1–0 in extra time in the
German Cup. He was sacked on 6 October 2006. His final match was a 4–2 win against
1899 Hoffenheim on 29 September 2006. On 2 January 2007,
Wacker Burghausen appointed him as their manager. His first match was a 2–1 loss to
Karlsruher SC on 21 January 2007. He left the club on 30 June 2007 when his contract expired. Wacker Burghausen finished in 17th place and were relegated. Six months later, on 11 December 2007, he was appointed manager of
SpVgg Weiden. He finished the
2007–08 season with a record of six wins, four draws, and four losses. Weiden won promotion during the 2008–09 season, finishing in first place, finishing nine points ahead of
TSV Aindling. He was with Weiden until 9 February 2010. His final match was a 1–0 win against
1. FC Nürnberg II on 13 December 2009.
2010–15: Wehen Wiesbaden, Arminia Bielefeld and Duisburg On 9 February 2010, Gino Lettieri joined
Wehen Wiesbaden of the
3. Liga. but they managed to avoid relegation by eight points. On 21 October 2010, Lettieri signed a new contract keeping him at the club until 30 June 2013. During the
2010–11 season, Wehen Wiesbaden narrowly missed out on the promotion playoff by a single point. Wehen Wiesbaden started the
2011–12 season with a 2–1 win against
Werder Bremen II on 23 July 2011. On 15 February 2012 with the club dangerously hanging round the relegation zone, SV Wehen sacked him, and replaced him with
Peter Vollmann the next day. Lattieri finished with a record of 31 wins, 21 draws, and 26 losses. He then became assistant coach of
Arminia Bielefeld from 2012 to 2014. He made his debut in a 3–1 loss to
Jahn Regensburg on 26 July 2016. During the
2014–15 season, Duisburg defeated
1. FC Nürnberg 1–0 in the first round of the
German Cup. However, they lost to
1. FC Köln in the second round of the German Cup on penalties after the match had finished in a 0–0 draw. Other results during the season include a 4–3 win against
1. FSV Mainz 05 II on 6 August 2014, a 3–1 win against his former club Wehen Wiesbaden on 29 November 2014, a 4–2 loss to
Arminia Bielefeld on 15 February 2015, and a 4–1 win against
Borussia Dortmund II on 21 March 2015. On 16 May 2015, Duisburg secured promotion to the
2. Bundesliga with a game to spare, after defeating
Holstein Kiel 3–1. They finished the season in second place. Duisburg started the
2015–16 league season with two draws and seven losses. They were also knocked out of the
German Cup by
FC Schalke 04 who had defeated Duisburg 5–0. Lettieri was relieved of his duties on 2 November 2015, his final match was a 1–0 loss to
1860 Munich. Duisburg were in 18th and last place at the time of the sacking. He finished with a record of 22 wins, 15 draws, and 17 losses.
2017–24: FSV Frankfurt, Korona Kielce, Return to Duisburg and FK Panevėžys On 7 March 2017, he was appointed as the new manager of
FSV Frankfurt als a successor to
Roland Vrabec. He received a contract until the end of the
2016–17 season and was tasked with preventing the club's relegation from the
3. Liga. Since this goal was not achieved and FSV Frankfurt got relegated, he left the club the end of the season. In May 2017, he signed a contract with
Ekstraklasa side
Korona Kielce. In September 2019, Lettieri was sacked by Kielce after the team lost four games in a row. Lettieri returned to MSV Duisburg on 11 November 2020 as the successor of
Torsten Lieberknecht. He was sacked on 27 January 2021, after the team only won two out of twelve games under his lead. In October 2021, he joined Greek club
AEK as an assistant under head coach
Argiris Giannikis. In March 2022, both coaches left their positions at the club by mutual agreement. In September 2022, Lettieri was appointed as the new coach of Lithuanian club
FK Panevėžys, replacing
Valdas Urbonas. At the end of the
2023 season, Panevėžys secured the first place in the
A Lyga, twelve points ahead of second place team
FK Žalgiris, becoming Lithuanian champions for the first time in history. On 26 January 2026, Lettieri was appointed as the head coach of
China League One club
Meizhou Hakka. ==Managerial statistics==