The 19-year-old Mokoena had a breakout season in the SA20, sitting fifth in the top wicket-takers list with 13 scalps in 10 matches for the Paarl Royals.
The fast bowler is one of five new caps in the 15-man with Connor Esterhuizen, Dian Forrester, Jordan Hermann and Eathan Bosch also selected.
Proteas head coach Shukri Conrad said: "Nqobani showed during SA20 that he is an exciting young quick with the ability to make an impact and this series will give him the perfect opportunity to expose him to the international setup."
Keshav Maharaj will lead the side, with the spinner one of only three players that is currently at the T20 World Cup due to workload and IPL commitments.
Fast bowler Gerald Coetzee makes his return to the T20I side for the first time since featuring against Namibia in October 2025, while Tony de Zorzi is back in the squad following his recovery from a right hamstring injury.
Conrad added: "With this series taking place directly after the T20 World Cup, the majority of that squad will return home, which creates a great opportunity for this group of players to step into the international environment and show what they're about at this level.
"Keshav has experience captaining the Proteas and has led two teams to the SA20 finals. His leadership and calm presence make him the ideal person to lead this group on this tour.
"The batting unit is particularly exciting for this tour. Tony brings experience to the top order, while Connor, Dian and Jordan have all demonstrated the ability to play positive, attacking cricket for their domestic teams."
The series will be played as double-headers, with the Proteas Women taking to the field in the afternoon before the men's encounter in the evening across all five matches - a first for the senior national teams.
The Proteas mentor said: "Touring New Zealand will challenge their skills in different conditions, and playing in our first bilateral double-header series alongside the Proteas Women adds to the excitement."
Proteas T20I squad: Keshav Maharaj (captain), Ottneil Baartman, Eathan Bosch, Gerald Coetzee, Tony de Zorzi, Connor Esterhuizen, Dian Forrester, Jordan Hermann, Rubin Hermann, George Linde, Nqobani Mokoena, Andile Simelane, Lutho Sipamla, Prenelan Subrayen, Jason Smith
Former India cricketer Aakash Chopra has identified Varun Chakaravarthy and Jasprit Bumrah as the key figures for India ahead of their T20 World Cup 2026 Super Eight clash against South Africa.
South Africa completed the group stage of the 2026 T20 World Cup undefeated when they eased past the United Arab Emirates by six wickets in New Delhi on Wednesday.
Aiden Markram said South Africa are moving closer to their best form at the ICC Men's T20 World Cup after a convincing seven-wicket win over the New Zealand national cricket team.
The Proteas made it three wins from three at the T20 World Cup after a thumping seven-wicket victory against New Zealand with more than two overs to spare in Ahmedabad on Saturday.
