Lauzon began training at the age of 14. He made his Ultimate Fighting Championship (UFC) debut at UFC 64: Unstoppable, losing to Spencer Fisher. At 18 years, seven months and 14 days old, Lauzon was the youngest fighter ever to appear in the UFC.
Lauzon is sponsored by TapouT and appeared in an episode of the television series TapouT. The TapouT crew followed Lauzon through the final preparations for his fight with Frank Latina. While filming, the crew expressed doubts about Lauzon's trainer and introduced him to crosstown rival trainer Mark DellaGrotte. After the episode aired, Lauzon's brother Joe criticized the episode and the TapouT crew's actions.
Lauzon was originally scheduled to fight Chris Horodecki at the Affliction: Day of Reckoning event on January 24, but Chris was denied his license for failing his physical.  Bobby Green stepped up to take Horodecki's spot against Lauzon. Lauzon claimed he was kicked and kneed to the groin a total of three times, a fact openly questioned by bloggers, internet forums and live by the broadcast team, in special by Tito Ortiz, who was doing Color Commentary for the event, at one point he claimed "Dan is Faking", referee Herb Dean and the doctor at one point asked to Dan Lauzon if he wanted to continue to fight, the fight was eventually restarted with Bobby Green having 2-points deducted while crowd loudly booed the point-deduction. While Bobby Green's unorthodox style managed to give Dan difficulties on the feet, Lauzon manage to control the fight on the ground and make Green tap out due to a Rear-naked Choke with five seconds left in the first Round.
As a result of the demise of the Affliction fight organization, Dan became a free agent, and as of July 28, 2009, is under contract with the UFC.
Dan Lauzon faced Cole Miller on January 2, 2010 at UFC 108, in a back-and-forth fight, Miller locked a Kimura from an Inverted Triangle position, such submission earned him a US$50.000 "Submission of the Night" bonus. At the same night and at the same event, Dan's brother, Joe Lauzon also lost his fight, after the event, probably because of the fact that both brothers lost, Joe Lauzon said that a fight between them, or even at the same event, is "not an option anymore".
Dan has trained with Efrain Escudero in the past. When Dan was 18, he lived and trained with Drew Fickett's Team Scrub in Arizona for 3 or so months. Recently in an interview this is what Dan had to say about his former training partner, friend, and opponent, Efrain Escudero.
"Facing Efrain [Escudero] is going to be a little awkward, fighting my former training partner. I did three hard training camps with him. Two of the times it was me and him both getting ready for fights in RITC, the other was getting Drew Fickett ready for his fight with Kurt Pelligrino.
“We know so much about each other’s game. I feel my game has changed so much since we trained together and I feel his game has stepped up, in a sense he's gotten so much better at everything he does, but he still has that strong wrestling base.
“For some people it may be hard to punch a friend, for me, this is a sport, I train with my own brother on a regular basis and have no problem punching him in the mouth, so I won't have a problem punching Efrain. It's just going to be a little awkward, but I want to win and I know he wants to win. I know he's not going to be pulling any punches and neither will I.”
|Professional record breakdown|
|20||12 wins||3 losses|
|Efrain Escudero||UFC 114||05/29/2010||Las Vegas, Nevada, USA|
|Loss||Cole Miller||Submission (Kimura)||UFC 108: Evans vs. Silva||1/02/2010||1||3:05||Las Vegas, Nevada, United States|
|Win||Bobby Green||Submission (Rear Naked Choke)||Affliction: Day of Reckoning||1/24/2009||1||4:55||Anaheim, California, United States|
|Win||Justin Hammertrum||TKO (Punches)||WCF 5||11/14/2008||1||0:45||Wilmington, Massachusetts, United States|
|Win||Brendan Hoxie||TKO (Punches)||WCF 4||6/20/2008||2||3:45||Wilmington, Massachusetts, United States|
|Win||Frank Latina||Submission (Triangle Choke)||WCF 3||2/8/2008||1||3:10||Wilmington, Massachusetts, United States|
|Win||Andrew Montanez||TKO||Wild Bill's Fight Night 13||1/25/2008||1||1:48||Atlanta, Georgia, United States|
|Win||David George||TKO||CZ 24 - Combat Zone 24||10/13/2007||1||2:46||Revere, Massachusetts, United States|
|Win||Wayne Harnois||KO (Punches)||WCF 1||09/21/2007||1||0:14||Wilmington, Massachusetts, United States|
|Win||James Meal||TKO||FFP Untamed 14||06/16/2007||2||3:57||Plymouth, Massachusetts, United States|
|Loss||Deividas Taurosevicius||Submission (Rear Naked Choke)||CFFC 3: Battleground||01/19/2007||2||1:15||Atlantic City, New Jersey, United States|
|Loss||Spencer Fisher||TKO (Strikes)||UFC 64: Unstoppable||10/14/2006||1||4:38||Las Vegas, Nevada, United States|
|Win||Dyrell Walker||Submission (Triangle Choke)||CZ 17: Take Control||08/5/2006||1||3:52||Revere, Massachusetts, United States|
|Win||Leonard Wilson||Submission (Choke)||RITC 84: Celebrity Theatre||07/1/2006||2||1:34||Phoenix, Arizona, United States|
|Win||Jason Harris||Submission (Choke)||RITC 83: Rampage||06/10/2006||1||N/A||Scottsdale, Arizona, United States|
|Win||Athony Peters||Submission (Toe Hold)||WFL 6 - Real: No Fooling Around||04/1/2006||2||2:20||Revere, Massachusetts, United States|
- ↑ JoeLauzon.com - The Tapout Show with Dan was Garbage
- ↑ CSAC denies Horodecki his license. MMAMania.com (January 21, 2009). Retrieved on January 21, 2009.
- ↑ http://www.sherdog.net/forums/f61/dan-lauzons-8-headed-c-ck-906788/
- ↑ http://forums.mmaweekly.com/showthread.php?t=16695
- ↑ Bobby Green to replace Horodecki. MMAWeekly.com (January 22, 2009). Archived from the original on January 29, 2009. Retrieved on January 22, 2009.
- ↑ Template:Cite news
- ↑ http://archive.is/20120712063447/mmajunkie.com/news/17417/ufc-108-salaries-rashad-evans-earns-top-fighter-payday-with-375k.mma
- ↑ http://archive.is/20120713172152/mmajunkie.com/news/17882/joe-lauzon-says-fight-with-brother-no-longer-an-option-boston-slot-his-for-taking.mma