The left-handed Londoner defeated Iskandar, the 2004 champion, 11-9, 11-5, 11-5 in 40 minutes to reach the 16th PSA Tour final of his career.
Grant, a former world No12 who is currently ranked 16 in the world, will face Cameron Pilley in Sunday's final after the sixth-seeded Australian downed eighth seed Mansoor Zaman in the other semi-final. The Pakistani retired injured only a few minutes into the fourth game with the score standing at 9-11, 11-10 (2-0), 11-3, 2-0.
Pilley, the 23-year-old world No24 from New South Wales, is celebrating his first PSA final appearance since September last year, but the 15th of his career.
Hopes of Malaysian success in the women's event were kept alive by world champion Nicol David, the No2 seed from Penang who repeated her victory over Rachael Grinham in the Qatar Airways Challenge final earlier in the month by beating the fourth seed 10-8, 9-6, 9-4 in 56 minutes.
There was Grinham disappointment in the other women's semi-final when third seed Natalie Grinham, the reigning Commonwealth Games champion who is Rachael's younger sister, bowed out to England's Tania Bailey in the day's longest match.
Bailey, the British champion from Stamford in Lincolnshire, produced her second upset in two days after battling for 73 minutes to beat Grinham junior 9-7, 9-7, 7-9, 1-9, 9-3. The 26-year-old world No8, who knocked out Vanessa Atkinson in the quarter-finals in her first win in five matches over the world number one, is celebrating her 11th WISPA World Tour final appearance - while David is now in her 24th.
RESULTS: CIMB Malaysian Open Squash Championships, Bukit Jalil, Kuala Lumpur, Malaysia
Men's semi-finals:
[3] Adrian Grant (ENG) bt [1] Mohd Azlan Iskandar (MAS) 11-9, 11-5, 11-5 (40m)
[6] Cameron Pilley (AUS) bt [8] Mansoor Zaman (PAK) 9-11, 11-10 (2-0), 11-3, 2-0 ret. (32m)
Women's semi-finals:
[8] Tania Bailey (ENG) bt [3] Natalie Grinham (AUS) 9-7, 9-7, 7-9, 1-9, 9-3 (73m)
[2] Nicol David (MAS) bt [4] Rachael Grinham (AUS) 10-8, 9-6, 9-4 (56m)