The unit returned to Camp Pendleton in mid-2005 and prepared again to deploy in 6 months. They departed Camp Pendleton beginning on January 21, 2006. They were operating in Fallujah but in March, C Company along with MAP 3 Wpns Company began operations in the area around Abu Ghraib prison which is located about west of Baghdad. After two and a half months, Charlie Company returned to the Camp Fallujah area and the entire battalion was re-united in Karmah. C Company later moved to Saqlawiyah to replace 1st Battalion, 25th Marines. The battalion completed their deployment and returned to Camp Pendleton in mid-August 2006. 1/1 suffered 17 KIA'S on this deployment and more than 50 wounded.