* China imported 100 mln T of iron ore in January
* Just below record 102.8 mln T in September
* Mills restocked ore ahead of holiday, lifting of curbs
* January steel exports hit nearly 5-year low (Adds steel export data, analyst comment)
SHANGHAI/MANILA, Feb 8 (Reuters) - China's iron ore imports jumped to the second highest level on record in January as the world's top buyer built stockpiles ahead of the Lunar New Year holiday and the lifting of steel production curbs next month.
Shipments of the steelmaking raw material in January climbed 19 percent from December to 100 million tonnes, customs data showed on Thursday.
The January number was just below the record 102.8 million tonnes that arrived in September. It was also up from 91.99 million tonnes that arrived in January last year.
Analysts had expected iron ore shipments to rebound in January, given that December's imports of 84.14 million tonnes had come in well below estimates.
"There's also strong demand, restocking before the holiday and some mills were also preparing for restarts after the winter season," said Wang Di, analyst at CRU in Beijing.
China is set to lift steel production curbs across 28 cities in mid-March as the winter heating season ends. Beijing imposed the restrictions from November as part of its campaign to fight air pollution.
January's import number was not too far above the 93.7 million tonnes recorded for the month on Thomson Reuters ship-tracking data, underlining efforts of mills to replenish inventories.
Bai Jing, analyst with Galaxy Futures, said iron ore traders booked shipments in October for January shipments.
"It's because supply was seasonally tighter in the first quarter and on expectation that steel mills would resume production in March," said Bai.
China's iron ore imports rose to a record 1.075 billion tonnes in 2017, exceeding 1 billion tonnes a second straight year.
Chinese steel exports slumped 18 percent to 4.65 million tonnes in January from the previous month, customs data also showed.
The shipments were down 37 percent from a year ago and at the lowest since February 2013.
"Chinese steel prices jumped quickly in November and early December so mills had no interest for exports, which was reflected in January shipments," said Qiu Yuecheng, an analyst with steel trading platform Xiben New Line E-Commerce in Shanghai.
"The output curbs also affected sales abroad," Qiu said.
China imported 1.19 million tonnes of steel products in January, up 9 percent from a year ago, the data showed.
China's steel exports for all of last year fell 30.5 percent to 75.4 million tonnes. Full-year imports stood almost steady at 13.3 million tonnes. (Reporting by Ruby Lian in SHANGHAI and Manolo Serapio Jr. in MANILA; Editing by Richard Pullin and Tom Hogue)