* Imports hit by holiday and bad weather, as well as demand slump
* Coal imports drop 21 pct on month and 30 pct on yr
* Soy, copper and crude also fall on month (Adds detail, wraps up other commodity imports)
BEIJING, Nov 8 (Reuters) - China imported 75.52 million tonnes of iron ore in October, down 12.3 percent from the previous month, official data from China's customs authority showed, with National Day holiday disruptions compounded by a slowdown in the domestic steel industry.
Slowing economic growth in China has had a massive impact on heavy industries like steelmaking and power generation, leading to a slump in demand for bulk commodities like iron ore and coal.
Iron ore imports in October were down 4.9 percent on the year, while shipments for the first 10 months of the year have reached 774.5 million tonnes, down 0.5 percent compared with last year, despite a huge crash in prices and a decline in high-cost domestic production.
Coal shipments in October, including lower-grade lignite, reached 13.96 million tonnes, down 21.4 percent from September and 30.7 percent from a year ago. Volumes for the year so far reached 170.3 million tonnes, down 29.9 percent compared with the same period of last year.
Domestic steel mills have been struggling with weak demand and product prices now at multi-decade lows, and have relied on the export market to help absorb surplus production.
However, despite complaints that China continues to dump large amounts of cheap steel on overseas markets, exports in October actually fell 19.8 percent to 9.02 million tonnes.
October crude oil deliveries fell 5.7 percent from September to 26.35 million tonnes, amounting to 6.2 million barrels per day.
Copper imports also declined 8.7 percent compared with last month, reaching 420,000 tonnes. Traders said imports had been affected by lukewarm domestic demand. Importers also arranged more deliveries in the previous month to compensate for the week-long October holiday.
Arrivals of anode, refined copper, alloy and semi-finished copper products reached a 20-month high of 460,000 tonnes in September.
Soybean imports also declined 23.8 percent on the month to 5.53 million tonnes, customs data showed, matching expectations, with supplies from South America in decline and production from North America still in transit.
With U.S. deliveries now starting to arrive, imports are likely to pick up to about 7 million tonnes in November, the China National Grain and Oils Information Centre (CNGOIC) said.