Industrial output rose 5.3 percent in January-February, the National Bureau of Statistics (NBS) said, less than expected and the slowest pace since early 2002.
Analysts polled by Reuters had expected it to rise 6.0 percent, edging up marginally from 5.9 percent in 2018.
The Chinese economy slowed in the fourth quarter of 2018, registering 6.6 percent growth for the whole year, the NBS said.
China's own official factory survey, which is seasonally adjusted, showed manufacturing output contracted in February for the first time since January 2009.
China's manufacturers are facing weaker sales at home and overseas, with exports hit by USA tariffs on Chinese goods and cooling global demand.
Private-sector fixed-asset investment, which accounts for about 60 percent of overall investment in China, rose 7.5 percent in the same period, compared with an 8.7 percent rise in 2018, data from the National Bureau of Statistics showed.
Retail sales increased by 8.2 percent year-on-year in the same period, unchanged from December, while industrial output went up 5.3 percent.
That processing rate works out at about 12.68 million barrels per day (bpd), according to Reuters calculations based on the NBS data, exceeding the previous daily high hit in September at 12.49 million bpd. The agency failed to provide monthly breakdowns of the output because of the week-long celebration of the Lunar New Year Holiday in early February. Economists are expecting further easing measures by the Chinese government to spur business activity.
Xining, the capital of Qinghai province in central China by the Tibetan Plateau, was the top performer last month with a monthly price increase of 2.3 percent. Retail sales rose 9 percent from one year earlier to 38.1 trillion yuan (about 5.7 trillion US dollars) in 2018.
China's state planner announced measures in January to boost consumption of goods ranging from eco-friendly appliances to big-ticket items such as cars, but the size and scope of the subsidy scheme is still unclear.
On an annual basis, home prices rose 10.4 percent in February, accelerating from a 10.0 percent gain in January.
"The growth trend of the modern service industry is relatively good", Mao said, adding that information transmission, software and information technology industries maintained a high growth rate of 26.5 percent.