Sprinter Gay, 31, earned a 12-month ban - halved from two years by the United States Anti-Doping Authority - after testing positive to an anabolic steroid, but will resume his career in Switzerland against another former doper, Justin Gatlin.
The presence of the two controversial Americans has rustled feathers in the athletics community, but Gay released a statement saying he was excited to get his 2014 campaign underway.
"Lausanne has always been one of my favourite meets, and I'm thrilled to have it be my opening meet of 2014," the statement read.
"I have run fast times here. I have been training for several months, and will be ready on July 3."
Gay won at the Lausanne meet in 2013, in a time of 9.79 seconds before serving his ban.
Also returning to the track is Jamaica's Yohan Blake, who will compete in the 200m after overcoming injury.
"I feel good. I'm going to enjoy running my 200m," Blake said upon arrival in Switzerland.
Blake's compatriot Veronica Campbell-Brown is in peak condition heading to the meet, after winning the Jamaican national title in the women's 100m.
"I always enjoy to be here. Today I did a light training session, take my marks in the stadium," Campbell-Brown said on Monday.