China Mobile has reported a 3.5% year-on-year increase in March quarter profit to 27.8 billion yuan (€3.3 billion).
The result missed the expectations of analysts polled by Bloomberg as a result of increased spending on customer retention costs.
Sales grew 7.8% to 127.4 billion yuan, but this was below the median analysts' estimates of 128.2 billion yuan.
China Mobile, the world's biggest mobile operator by subscribers, has been investing heavily in networks, subsidies and marketing in a bid to draw more 3G users.
As of the end of March, China Mobile had 667.2 mobile customers, including 59.5 million 3G users. Net additions for the quarter were around 5.7 million.
But because the company is lumbered with the non-standard, homegrown TD-SCDMA standard for 3G, the company has been unable to officially offer popular smartphones including the iPhone. This is starting to erode the company's market share lead over its rivals.
The company is betting heavily on TD-LTE to help it win back some of this share, once it receives the licenses needed to launch 4G in mainland China.
China Mobile is due to launch TD-LTE in Hong Kong this week, through its subsidiary China Mobile Hong Kong. This network will operate on the 2.6-GHz band.