In a statement, Cricket Scotland said: 'Everyone at Cricket Scotland is devastated at the sad news of the death of Con De Lange on April 18 at age 38. South Africa-born all-rounder De Lange was diagnosed with a brain tumour after falling ill while away on worldwide duty in late 2017.
He captained Scotland to its first 50-over victory over an ICC full member in May 2017, hitting the winning runs as his side chased down 287 against Sri Lanka.
De Lange played his last worldwide in November 2017 in an ODI against Papua New Guinea.
In October past year, his family revealed the cricketer's ailment and also launched a campaign to raise money for the brain tumour society.
South Africa's greatest fast bowler Allan Donald, now Kent's bowling coach, tweeted: "Gutted to hear that Con De Lange has passed away this morning".
A Cricket Scotland statement hailed de Lange as a "great servant" of Scottish cricket across levels.
Cricket Scotland said past year that De Lange was being treated for a brain tumour.
"But above all, we remember Con the man - competitive, committed and the ultimate team player, someone with unshakeable principles and integrity".
According to some sources it has been said that Con De Lange was facing this problem from over a year.
Con is survived by his wife Claire and their two children, Daisy and Rory.
De Lange began his career in his native South Africa, where be played for Boland before stints with Cape Cobras, Knights and Free State.
"Everyone at NCCC sends sincerest condolences to his family and friends at his hugely sad time".
His diagnosis with brain cancer came as a shock to those in the cricketing world, but by all accounts the all-rounder fought hard to against the disease. "He will be greatly missed and very fondly remembered by many throughout the world of cricket", he added. One of the nicest blokes you could meet gone far too soon. Thoughts and prayers go out to his friends and family.