"China has sent at least 18 truckloads of arms and ammunition to Nepal via the Kodari highway (northeast of Kathmandu)," the independent Kantipur daily said on Friday.
Nepal's army said it had no comment on the report.
Nepal has looked to China for arms to combat the Maoist revolt after India, the nation's biggest arms supplier, the US and Britain suspended military aid following King Gyanendra's seizure of power nine months ago.
"China had been providing Nepal with non-lethal equipment like telecommunication sets in the past but this is the first time it has provided guns and ammunition to Nepal," the newspaper said.
"On Tuesday, 12 trucks entered Nepal while the following day, six more vehicles carrying arms entered Nepal from Khasa in Tibet," the daily reported, citing unidentified sources.
An army spokesman declined to comment on the report which did not identify the nature of the weapons.
"Since it concerns the security of the nation, no comment," army spokesman Dipak Gurung told AFP.
King Gyanendra seized power
nine months ago
Gyanendra dismissed the government on 1 February and cracked down on civil liberties, saying the move was necessary to end the insurgency.
The Maoists, who take their inspiration from former Chinese revolutionary leader Mao Tse-tung, declared a three-month truce in September.
The began their insurrection in 1996 with the aim of toppling the monarchy and installing a communist republic.
This week, a seven-party opposition alliance and the Maoists announced an agreement to launch a joint movement to restore democracy in Nepal under which the guerrillas would lay down their arms and join the political mainstream.
Details of the pact, however, still have to be formalised.
"The Chinese army escorted the trucks carrying arms to the Nepal-China border and handed them over to Nepalese army in plainclothes and transferred the goods to civilian trucks when they entered Nepal," the Kantipur daily said.
In October, China, an important donor to impoverished Nepal, promised almost $1 million in help to its army to crush the insurrection that has claimed more than 12,000 lives.
Royal Nepal Army chief of staff General Pyar Jung Thapa won the pledge on a visit to Beijing where Chinese leaders threw their support behind the fight against the guerrillas.