The 15-man squad led by Angelo Mathews completed a week- long training session and will have three days of rest in Colombo before leaving for London on Thursday.
They went through strength and altitude training in the central hill region of Kandy, 500 metres (1,65 feet) above sea level, to prepare for conditions in England, Sri Lanka Cricket said.
"Over the past months many of us have not been able to play together consistently as a team due to injury or other factors," Mathews said in a statement.
Earlier this month, the cricket board secured the services of famed South African paceman Allan Donald an interim bowling coach.
Donald has declared that the Sri Lankan squad had the potential to win the next the Champions Trophy.
Sri Lanka head coach Graham Ford, a fellow South African, has been preparing the Sri Lankans for the 50-over tournament starting June 1.