During his five-day official visit, Rajapaksa will lead the Sri Lankan delegation to the 68th UNGA, where he is scheduled to address the gathering on Tuesday amid international concerns over human rights and reconciliation after the end of the civil war with the LTTE in 2009.
This is the sixth time Rajapaksa is attending the UNGA. He first addressed the UNGA in 2006 and the last in 2011.
He is scheduled to participate in a number of bilateral discussions with the UN Secretary-General Ban Ki-moon, Commonwealth Secretary-General Kamalesh Sharma and several heads-of-state from Africa, the Middle East and Asia, Sri Lanka's official news portal said.
His visit comes after his party United Peoples Freedom Alliance (UPFA), suffered major electoral setback at the hands of Sri Lanka's main Tamil party Tamil National Alliance (TNA) in the former LTTE strongholds.