The shares opened at 35.2 riyal ($9.39) apiece, 10% above their initial public offering price (IPO) of 32 riyals.
Saudi Arabian Oil Co (Aramco) raised a record $25.6 billion in its IPO last week, giving it a market value of around $1.7 trillion.
That makes is comfortably the world's largest listed company, although it will have one of the smallest "free floats" of publicly traded shares, at just 1.5%.
The flotation, a major challenge for the Riyadh stock exchange, propels the bourse into the world's top 10 by value of listed companies,
Saudi Arabia relied on mainly domestic and regional investors to buy Aramco shares after lukewarm interest from abroad.
The $25.6 billion of proceeds beat Chinese tech firm Alibaba's $25 billion listing in 2014.
(Reporting by Saeed Azhar; Editing by Mark Potter)