Orders to factories edged up 0.1 percent in November, the weakest showing in three months, the government reported yesterday.

The report prompted some concern about a possible slowdown in manufacturing following the October stock market collapse.

The Commerce Department said orders for both durable and nondurable goods rose to $209.66 billion in November after increases of 1.3 percent in October and 1.8 percent in September.

The November gain was the poorest performance since orders fell 1.4 percent in August, which was only the second decline this year.

Some economists said they were particularly concerned about an 18.5 percent plunge in orders for computers and other office equipment, suggesting that it may reflect concerns on the part of businesses about the impact of the Oct. 19 stock market collapse.

"That decline could be an early warning signal," said David Wyss, an economist with Data Resources Inc. in Lexington, Mass. "Personal computers have about the shortest lead-time of any investment good. It is an easy place to cut back if you are nervous."

The fall in computer orders contributed to a 2.4 percent decline in the overall business investment category of nondefense capital goods, a setback analysts said would be worrisome if it continues.

Economists are pinning most of their hopes on the ability of the economy to avoid a recession in 1988 on continued strong growth in business investment and export sales, two bright spots in the economy in 1987.

Lawrence Chimerine, chairman of the Wefa Group, formerly Wharton Econometrics, said he did not find the one-month drop in business investment orders particularly worrisome.

He said the overall orders figures were still at relatively high levels, reflecting the boost U.S. manufacturers have received all year long from a weaker dollar, which has made their products competitive again on overseas markets.

"This report is consistent with a pattern of exports improving while the domestic economy has been slowing. It will be a tug-of-war between those two forces to see which wins out next year," Chimerine said. "I think we will squeak through without a recession, but the risk of one is quite high."

The strength in exports has helped push total orders up by 7.2 percent in the first 11 months of 1987, compared with a 0.6 percent decline in manufacturing orders for all of 1986.

Orders for durable goods, items expected to last three or more years, fell 0.4 percent in November to a seasonally adjusted $115.65 billion, the government said.

This represented a revision from a report a week ago that said orders had risen by less than 0.1 percent for the month.

The weakness in durable goods was offset, however, by a 0.7 percent increase in orders for nondurable goods, to a seasonally adjusted monthly total of $99.01 billion.

Orders for military equipment edged down 0.4 percent to $9.96 billion. Without this decline, total orders would have been up 0.2 percent for the month.

Orders for transportation equipment were up 0.7 percent to $28.79 billion.

Other sectors showing increases included primary metals such as steel, which posted a 1.2 percent rise to $10.57 million.

Orders for machinery including household appliances posted a 1.6 percent rise to $20.32 billion, while the machinery category that includes computers fell 6.8 percent to $17.66 billion.

Shipments of manufactured goods increased 0.5 percent in November to $207.3 billion.