Dawson made his Leyton Orient debut, starting the whole game, in a 2–1 defeat to Yeovil Town in the opening game of the season. Since making his debut, he established himself in the starting eleven and played in every matches from the beginning until he suffered a groin injury, resulting him being on the substitute bench to heal his injury and eventually his illness. However, during 3–0 win over Bristol Rovers, in which he set up one of the goals, Dawson received a horror tackle from Carl Regan, resulted him being substituted, which he described it as "a leg-breaker." Dawson scored his first goal for the O's on his return in their 2–1 win against Tranmere Rovers on 11 December 2010. For his performance, Dawson was named League One's Team of the Week. It wasn't until on 8 February 2011 when he scored his second goal, in a 3–0 win over Swindon Town. Weeks later on 20 February 2011, Dawson played a vital role throughout a 1–1 draw against Arsenal in the 5th round of the FA Cup, naming him Man of the Match; but lost 5–0 in the FA replay. Despite suffering from another injury, Dawson finished his first season at Leyton Orient, making the total of 50 appearances and scoring 2 times in all competitions.