Improving first-quarter results from some of China's biggest steel and cement firms suggest that Beijing's economic recovery plan may be starting to filter through into corporate profits.

That would bring a leavening touch to data released this week indicating that China's factories are expanding less quickly than expected, more evidence that the pace of recovery is slowing despite a boom in credit supply.

Earnings growth for China-listed companies averaged 10.5 percent for the first quarter, a big improvement from losses in the same period last year of about 10 percent, but still short of the 16.5 percent expected, according to research from CLSA-Fortune Securities.

"Commodities-related companies have all shown some kind of improvement... but it's still very much a company-specific story at this point," said Shumin Huang, an investment manager with the Greater China team at JP Morgan Asset Management, who declined to make any specific stock mentions.

Most market watchers expect an increase in demand for building materials as the first quarter credit boom translates into fixed asset investment, which should pick up modestly in the second quarter as more infrastructure projects start.

Faced with the possibility of an A-share delisting were it to record a third straight annual loss, Angang Steel Co Ltd made 550 million yuan ($89.21 million), its first quarterly profit in more than a year.

Angang shares in Hong Kong are now down 19 percent on the year, versus a 4.5 percent slide on the China Enterprises Index of the leading Chinese listings in Hong Kong.

Although Angang has underperformed the H-share benchmark in the previous three years, it is still trading at 36 times its forward 12-month earnings, a 238.9 percent premium to its median, according to Thomson Reuters StarMine.

Lower fuel prices plus cost cuts the company started implementing in the fourth quarter last year helped. Standard Chartered analysts said Angang's steel inventory declined 10 percent from its peak in mid-March, but industry officials remain cautious.

Late last month, the China Iron and Steel Association warned its members to rein in expectations for the rest of the year. An anticipated increase in demand would not be enough to justify big rises in production in coming months, it said.