First Minister Nicola Sturgeon is attending the annual wreath laying and Remembrance Sunday service at St Giles' Cathedral in Edinburgh.
Military chiefs, emergency services and regimental associations also took part in the event, organised by veterans' charity Legion Scotland.
A two-minutes silence took place across the UK at 11:00 GMT.
Wreath laying was held at the Stone of Remembrance outside the City Chambers on the Royal Mile in the Scottish capital.
Ms Sturgeon said: "Remembrance Sunday is an opportunity for all of Scotland to join with others right across the world and commemorate those who made the ultimate sacrifice in conflicts during the last century and more recently."
Also attending the service in Edinburgh was Scotland Office Minister Andrew Dunlop and president of Legion Scotland, Sir Alistair Irwin.
Mr Dunlop said: "It is so important that we remember the servicemen and women who have made the ultimate sacrifice so that we can live freely, and to stand together on Remembrance Sunday to honour them."
Kevin Gray, Legion Scotland's chief executive officer, said: "Sadly as time moves on the memories become more and more inherited, so now more than ever is the time to ensure we take time to pause, reflect and remember."
In Glasgow, Legion Scotland representatives, serving military, clergy and civic leaders observed a two-minute silence at the cenotaph in George Square.
Lord Provost Sadie Docherty was joined at the event by Deputy First Minister John Swinney, Baroness Annabel Goldie, Scottish Labour leader Kezia Dugdale, Police Scotland Assistant Chief Constable Bernard Higgins and Scottish Fire and Rescue Service assistant chief officer Lewis Ramsay.
Aberdeen marked Remembrance Sunday with a ceremony in front of the city's war memorial on Schoolhill, with serving forces, reserves, veterans and cadets in attendance.
Lord Provost George Adam led the laying of wreaths before a church service at the Kirk of St Nicholas Uniting.
Events to remember servicemen and women who died in conflict are taking place across Scotland.