0325 GMT June 20, 2018
Output at factories and workshops expanded 6.2 percent on-year, the National Bureau of Statistics (NBS) said, slowing from 6.6 percent in September and below a forecast of 6.3 percent in a Bloomberg News survey.
AFP reported, the government has moved to wind down production at some steel factories and smelters in a drive to clean up the country's smog-ridden cities.
Factories also closed during last month's Communist Party congress, during which President Xi Jinping called for more efforts to protect the environment.
The government is also pushing to make domestic demand a growth driver of the world's second largest economy and make China less reliant on manufacturing and exports.
"Generally speaking, the national economy maintained stable performance with improved quality and sound momentum," NBS spokeswoman Liu Aihua told reporters.
"However, we must be aware that China is at a pivotal stage for transforming the growth model," she said, adding that "problems of unbalanced and insufficient economic development was acute".
The readings follow a surge in factory price figures last week.
The clean-air policy, which has been stepped up going into the winter when pollution worsens, has led to tighter supplies and in in turn lifting prices.
NBS data showed growth in retail sales slowed to 10 percent in October, down 0.3 percentage points from September and also short forecasts of 10.5 percent.
Fixed asset investment grew 7.3 percent on-year from January to October, in line with expectations.