The 24-year-old student-athlete, who has a diploma in business management from Nelson Mandela University and is now applying to do a post-graduate diploma in accounting, will be part of the foundation's programme for this year.
He is thrilled at the opportunity, saying it has been "long-time dream to be a member of the foundation".
"Joining the foundation is by invitation only and I have been hoping for some sort of recognition for around six years," said Van der Merwe, who has been playing for the Madibaz Golf Club for the past four years.
"I am so happy and thankful at receiving this chance and am determined to use the opportunity as best I can."
Van der Merwe is listed at No 18 in the South African amateur rankings and a shift in focus by the foundation from selecting only juniors for the programme to anyone in the amateur ranks paved the way for his invitation.
The Humewood Golf Club member, who has a handicap index of plus 4.3, will remain in Port Elizabeth to continue his studies, but will receive backing on a range of fronts from the foundation.
"I will get support in terms of being provided with new equipment and part of my studies will be funded by the foundation," said Van der Merwe.
"On top of that, I will receive funding to participate in the big amateur events around the country.
"Of course, there has to be some feedback from my side, so I have obligations to abide by as a member, but financially they help a lot and this is something I could not have done without them."
The Madibaz player, who represents Eastern Province and earned SA junior colours in 2014, has already reaped the benefits as a member of the programme.
"We played five tournaments in Johannesburg through January and February," he said.
"I made the cut at all the events and my best finish was coming fifth at the African Amateur strokeplay championship at Glendower Golf Club."
Madibaz Golf Club president, Karl du Preez, said they were delighted at Van der Merwe's selection for the foundation.
"As he will now be able to attend a number of important national amateur tournaments, he will be working hard on improving his SA ranking," said Du Preez.
"Madibaz golf and the Nelson Mandela University, as well as Humewood Golf Club, are extremely proud of Altin and his achievements and we wish him the best of luck for the year."
The Ernie Els Foundation was founded in 1999 with the purpose of identifying young talented individuals in golf, predominantly from families of limited resources, to provide educational assistance and playing opportunities.
The objective is to produce successful young leaders and to develop their playing ability to its full potential.