A second stock connection with mainland China which opened late last year has allowed even more money to flow onto the semi-autonomous city's exchange.
By Tuesday afternoon, Tencent's market capitalisation had reached 4.15 trillion Hong Kong dollars ($531 billion), surpassing the US social network's $519 billion.
The market movement made China's Tencent one of the world's top five most valuable companies, although it is still far short of leader Apple which is currently valued at $873 billion.
Tencent has nearly one billion users on its popular WeChat phone platform, where people can chat, post photos, play games, transfer money and pay for a variety of services in China.
The must-have app has revolutionised China's tech industry, with even the media and publishing sectors seeing changes to how Chinese consume and pay for content. Tencent's publishing-focused arm was spun off and listed in Hong Kong earlier this year.