Xiaomi's listing comes at a delicate time for Hong Kong's stock market, with the benchmark Hang Seng index falling 2.7 per cent last week and 5.8 per cent this year as investors fret over escalating trade tensions between the United States and China.
"Although the macroeconomic conditions are far from ideal, we believe a great company can still rise to the challenge and distinguish itself", he said in a speech at the listing ceremony.
It has become one of the world's largest smartphone-makers.
Xiaomi's IPO valued the firm, which also makes internet-connected home appliances and gadgets, at about $54 billion, nearly half the $100 billion it had initially hoped for and below its more recent target of at least $70 billion.
The weak pricing values the firm, which also makes internet-connected home appliances and gadgets, at about $54 billion, nearly half its original US$100 billion ambition earlier this year.
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Typically companies are valued on a multiple of profits or sales. Apple is trading at 16 times earnings and Chinese social media giant Tencent is trading at 36 times.
"Other IPO candidates will rush to Hong Kong to list before the market sentiment shifts". Others say the ongoing trade war between the US and China has spooked investors from putting money in Chinese companies.
"The market is really concerned about how much growth Xiaomi can generate in 2019, and whether the company can deliver" on what it pitched to investors, said Hao Hong, chief strategist at Hong Kong-based broker BOCOM International.
"The debut has been pretty solid given the headwinds they've faced coming in, including the size of the deal, the newness of what they're trying to do, CDRs (Chinese depositary receipts), dual-share class voting rights and trade wars".
Lei Jun also said, "Without the innovation of the Hong Kong capital markets, it would be hard for us to have a chance to list publicly in Hong Kong". Goldman Sachs Group Inc., Morgan Stanley and CLSA Ltd. are leading Xiaomi's IPO as joint sponsors.