The squad was announced by New Zealand Rugby Union President Bryan Williams at the Under 20 trial camp in Palmerston North today.
Rob Penney said the trial saw 46 in camp, vying for a spot in the travelling squad of 28.
"All the boys put in a really good effort, and the trial game held yesterday gave us a lot to think about.
"I'm really happy with the squad we have selected with a lot of young men putting their hands up for national team honours.
"We're really excited about heading to South Africa now to defend our title," he said.
The 2012 New Zealand Under 20 team is:
Junior Tafa Va'a
Bay of Plenty
Those unavailable for selection are Auckland's Gnafatasi Sua (injury) and TJ Perenara (Wellington) and Sam Cane (Bay of Plenty) due to Investec Super Rugby commitments.
The team will assemble again in Auckland on Friday 24 May ahead of travelling to South Africa on Wednesday 30 May.
The New Zealand Under 20 opens their tournament against Samoa on 4 June at Danie Craven Stadium in Stellenbosch.