It was the 14th straight month that the index was above 50 percent.

        The PMI includes a package of indices to measure manufacturing sector performance. A reading above 50 percent indicates economic expansion, while that below 50 percent indicates contraction.

        The figure stood at 56.6 percent in December 2009, the highest since May 2008, according to the CFLP.

        The new orders index rose to 59.3 percent, up 1.2 percentage points, in April from the previous month.

        Zhang Liqun, a researcher with the State Council's Development Research Center, said the growth in April's PMI was largely seasonal as the index had often been high in March and April in past years.

        He noted uncertainties still remain in the growth of exports and domestic demand, both of which were still partly buoyed by the government stimulus programs and had yet to enter a continuous growth trajectory.

        Zhang also said the climb in purchasing prices would be likely to burden enterprises with "notable" production costs.

        The PMI purchasing prices index surged to 72.6 percent, the highest level since the second half of 2008, up 7.5 percentage points from March.

        The PMI reading was based on data from the National Bureau of Statistics, covering purchasing and supply managers in more than 700 firms across China.