"On 24 October 2013, the Syrian Arab Republic submitted to the OPCW its formal initial declaration covering its chemical weapons programme," the watchdog said in a statement, adding that Damascus had had until today to do so.
Damascus was required to submit the destruction plan under a US-Russian deal agreed last month that headed off military strikes on Syria.
The accord also gives Syria up to mid-2014 to destroy its chemical arsenal.
President Bashar al-Assad's regime has already handed over an inventory of its chemical weapons and facilities, and international inspectors are already busy inspecting and destroying them.
"The document from Syria includes a general plan of destruction for consideration by the OPCW Executive Council," it added.
The OPCW's Executive Council will use the Syrian declaration to decide by November 15 on "destruction milestones" for Syria's arsenal.