* Implied oil demand at 9.71 mln bpd in April, up 1.1 pct on yr
* Jan-April oil demand at 9.9 mln bpd, up 0.4 pct on yr
* April refinery runs at 9.63 mln bpd, up 3.8 pct on yr, down 2.4 on mth
* April net fuel imports down 72 pct on yr
BEIJING, May 13 China's implied oil demand fell 0.8 percent in April from the previous month to its lowest since September as refineries scaled back production for maintenance and continued to export surplus fuel to trim inventories as the nation's economy slowed.
Chinese investment, retail sales and factory output growth all disappointed in April by hitting multi-year lows, suggesting the world's second-largest economy is still losing steam despite government efforts to shore up activity.
China consumed roughly 9.71 million barrels per day (bpd) of oil last month, according to Reuters calculations based on preliminary government data, the lowest level in seven months and down from 9.79 million bpd in March.
April consumption was up 1.1 percent from 9.6 million bpd a year earlier, the calculations showed, while for the first four months of 2014, oil demand climbed just 0.4 percent from a year ago to 9.9 million bpd.
"A slowdown in Chinese oil demand growth, that emerged mid-2013, has continued in line with the underlying macroeconomic trend. Demand for industrial fuels has been particularly soft," the International Energy Agency said in its April report.
The IEA forecast that China's total oil demand would log an increase of 348,000 bpd, or 3.4 percent, for the whole of 2014, according to the monthly report.
Reuters calculates implied oil demand using official refinery throughput data plus net imports of the main refined products, excluding changes in fuel stocks, which China rarely reports.
China's daily crude throughput in April fell back 2.4 percent to 9.63 million bpd, from 9.87 million bpd in March, while rising 3.8 percent from a year ago, data from the National Statistics Bureau showed.
Crude runs may be capped as refineries have entered the peak maintenance season. PetroChina Co Ltd shut its largest 410,000-bpd Dalian refinery for maintenance from April 10 to late May, industry sources have said.
Other plants conducting maintenance last month included Sinopec Corp's Changling and Shijiazhuang refineries, as well as PetroChina's Dagang unit, industry sources said.
Net fuel imports in April fell 72 percent from a year earlier to 79,333 bpd as oil firms kept exporting surplus fuel, customs data have showed.
China's crude imports rose more than a fifth in April from a year earlier to a record high of 6.78 million barrels per day (bpd), helped by higher seasonal demand and indications of stockpiling.
(1 tonne=7.3 barrels for crude conversion; 1 tonne=7 barrels for fuel conversion) (Reporting by Judy Hua and Chen Aizhu; Editing by Tom Hogue)