Stephen died in May 2014 at the age of 19, having been diagnosed with bowel cancer at the age of 15.
Jane Sutton celebrated reaching the peak of the highest mountain in Africa with a thumbs-up photo at the summit.
She wrote on social media the climb was "tougher than I anticipated" but the team reached the summit to watch a "spectacular sunrise".
Jane Sutton told ITV News before set off that she decided to undertake the challenge of climbing the tallest mountain in Africa, because her son had taught her to "seize every minute".
Stephen's battle with cancer caught the imagination of the general public after his "bucket list" campaign to raise £10,000 for the Teenage Cancer Trust was shared widely online.
His optimism and good humour touched people around the globe and Stephen raised more than £5 million for the charity.