* September industrial profits up 4.1 pct y/y vs 9.2 pct in Aug
* Softer profits due to slower sales, production
* Q3 GDP grew at weakest pace since global financial crisis (Adds more detail)
BEIJING, Oct 27 (Reuters) - Profit growth at China's industrial firms slowed for the fifth consecutive month in September as sales of raw materials and manufactured goods further ebbed, pointing to cooling domestic demand in the world's second-biggest economy.
The slowdown was in line with data last week that showed September's factory output grew at the weakest pace since February 2016.
Slowing corporate profits will put pressure on jobs, ultimately tapping the brakes on household consumption and hurting China's overall growth.
Industrial profits rose 4.1 percent in September from a year earlier to 545.5 billion yuan ($78.57 billion), the National Statistics Bureau (NBS) said on Saturday. That was less than half of the pace in August, and the slowest since March.
Earnings in September were mainly pressured by a greater slowdown in production and sales, declining price growth, as well as a high statistical base a year earlier, He Ping of the statistics bureau said in a statement accompanying the data.
An escalating trade war with the United States has also added to the pressure on overall output, and threatens to chill business investments and earnings growth in the months ahead.
Data last week showed the Chinese economy in the third quarter grew at the weakest pace since the global financial crisis as manufacturing output slowed.
The manufacturing sector has also been squeezed by a reduction in sources of credit amid Beijing's multi-year crackdown on corporate debt and risky lending practices.
While authorities are taking steps to ease pressure on firms with liquidity issues, many companies still face difficulty in obtaining funding. Interest rates on loans have also risen due to the reduced supply of credit.
A cooling property market - an engine of economic growth - has also sapped demand for construction-related goods and services, curbing industrial profits.
Softer infrastructure investment despite Beijing approving more projects in the second half this year has also added pressure on the bottom-lines of industrial firms.
In the first nine months of the year, industrial profits increased 14.7 percent, driven by earnings of companies producing steel, building materials, oil and petrochemicals.
But the growth slowed from the 16.2 percent pace seen in January-August.
Earlier this month, Jiangsu Shagang Co Ltd, the listed arm of China's biggest privately owned steel mill Shagang Group, reported a 91.5 percent increase in net profit for the third quarter.
The average profit margin for steel remains very high, according to analyst at Argonaut Securities in Hong Kong.
Industrial firms' liabilities rose 6.1 percent from a year earlier by the end of September to 63.1 trillion yuan, compared with an increase of 6.6 percent by end-August.
The statistics bureau's data covers large companies with annual revenues of more than 20 million yuan from their main operations.
$1 = 6.9425 Chinese yuan renminbi Reporting by Ryan Woo and Zhang Min; Editing by Michael Perry