The stock opened at 63 yuan, 9.4% higher than the offer price of 57.58 yuan, before paring gains over the course of the day to close 0.52% higher at 57.88 yuan.
The carrier's Hong Kong-listed shares closed 3.33% higher. The company said in a filing Tuesday that it would press ahead with a plan to buy back up to 2.05 billion shares, worth nearly $13 billion.
Tsz Wang Tam, an analyst at DBS Vickers in Hong Kong, said that the share buyback announcement had helped to boost the company's shares on Wednesday, but cautioned against reading too much into short-term share price performance.
China Mobile's debut was closely watched after a number of Chinese companies including BeiGene Ltd recently saw shares fall below their offering prices on the first day of trade.
The world's largest mobile network operator by total subscribers, China Mobile had sold 845.7 million shares at 57.58 yuan each in Shanghai.
China Mobile has said it plans to use proceeds from the offering to develop projects including premium 5G networks, infrastructure for cloud resources and intelligent ecosystems.
($1 = 6.3721 yuan)
(Reporting by Andrew Galbraith and Samuel Shen; Editing by Tom Hogue, Stephen Coates and Louise Heavens)
