Isha and Akash, 23, were appointed to the boards of Reliance Jio Infocomm Ltd and Reliance Retail Ventures Ltd, the company said.
Ambani, the world's richest energy billionaire, has three children -- Isha, Akash and Anant.
While Isha and Akash are twins, youngest sibling Anant is pursuing studies in US.
Isha, who graduated from the Yale University with majors in psychology and South Asian studies in 2013, worked with global consultancy firm McKinsey in US briefly.
Akash, who graduated from Brown University with major in Economics, had been working closely with Ambani family confidant Manoj Modi on RIL's 4G telecom venture.
The two are joining around the same age as their father Mukesh, who was 24 years old when he joined RIL in 1981.
While the Ambani scions have been seen at company's annual general meetings, Akash possibly made his first appearance on a company's business deal when RIL in 2011 signed agreement in London to sell 30 per cent stake in 23 oil and gas blocks including the producing KG-D6 fields to BP plc for $7.2 billion.
Isha first came under public limelight as a 16-year-old when Forbes ranked her number two in a list of the world's youngest billionaire heiresses.
The two enter the long list of scions joining family businesses.
Interestingly, a few of them had a stint at McKinsey or another consulting firm or a global bank before joining the family businesses.
Nandini Piramal, daughter of Swati and Ajay Piramal, worked with McKinsey as a business analyst before joining her family concern in 2006.
Rishad Premji spent a few years at Bain & Co in London before he joined Wipro.
Aditya Mittal started out in investment banking with Credit Suisse.
Image: Mukesh Ambani (R), chairman of Reliance Industries Limited, poses with his son Akash, daughter Isha (2nd L), wife Nita (C) and mother Kokilaben, before addressing the annual shareholders meeting in Mumbai June 6, 2013. Photograph: Danish Siddiqui/Reuters
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