Alessandrini, 27, joins the Galaxy after spending almost 10 years playing professionally in France.
“We are very excited to add a talented, attacking winger like Romain to our roster,” Galaxy general manager Peter Vagenas said in a club release. “He is in the prime of his career and has spent time playing at a top division in Europe. Romain will play a valuable role in our team’s success this season and we look forward to him joining the team ahead of the 2017 season.”
Prior to joining his hometown club Marseille, Alessandrini scored 20 goals and added 12 assists between 2012 and 2014 for fellow Ligue 1 side Stade Rennais. He tallied 11 goals and nine assists in his time with Marseille.
Alessandrini was called into the French national team in 2013, but had to withdraw due to injury and has yet to earn a cap for Les Bleus.
“This is the best club in the United States. It’s very fortunate for me to come here,” Alessandrini told the Galaxy's official website. “There were a lot of good players like [Steven] Gerrard and [David] Beckham, and for me, it was an inspiration to come here and play for this club. It was very good to sign for the Galaxy.”