China's assembly lines are humming with computers, refrigerators and automobiles this year.

Figures for industrial output in the first quarter show a 16 percent growth in total value over the corresponding period of 1987 to 264 million yuan (US$73 million).Computers led other manufacturing sectors with 65 units produced, 91 percent more than in the first three months of last year.

Noteworthy increases are reported in the production of 1.3 million household refrigerators (up 76 percent) as well as 136,800 automobiles (up 45 percent) and 598,000 cameras (up 41 percent).

A sort of frenzy is gripping consumers in China, who spend their savings - or borrow - to buy refrigerators, cameras, television sets and video recorders, the status symbols. Wedding portraits commonly feature couples posed alongside photographic displays of refrigerators, electric fans and TVs.

Greater economic prosperity combined with booming foreign trade also is enabling more companies to purchase cars, vans and trucks.

In the mid-1960s, there were so few cars on the road that courteous policemen switched traffic lights to green when they saw one approaching so it could breeze past without interruption.

China is now encouraging automakers to export parts and components and to produce more vehicles for the domestic market to curb imports. The value of vehicles exported last year rose 64 percent to $51 million, according to the latest figures.

China's longest computerized auto assembly line - stretching 830 feet - went into production last December. It is designed to make 10,000 cars, trucks and buses a year.

In the chemical sphere, output of ethylene jumped 52 percent to 322,000 metric tons, while that of pharmaceuticals rose 39 percent to 44,000 tons.

Against these proclaimed triumphs, China's official statistics for January- March reveal substantial decreases in a mixed bag of items compared with the first three months of 1987:

* Crude salt - 1.3 million metric tons, down 24 percent.

* Radios - 3.6 million sets, down 18 percent.

* Sugar - 2.8 million metric tons, down 16 percent.

* Watches - 13 million pieces, down 15 percent.

Drops also were registered for sewing machines, locomotives and washing machines.

Meanwhile, the Associated Press Friday quoted the official China Daily as saying Beijing will try to cut imports by specifying 100 machinery products, ranging from buses to air conditioners, that it wants to see produced at home.

The report said the list, to be made public this month by the Ministry of Machine-Building and Electronics Industry, also includes motorcycles and machines for the production of textiles, foods, medicines and refrigerators.

The 100 items all are produced by enterprises under the Ministry of Aeronautics Industry, which formerly was a supplier of military aircraft but now produces mainly civilian goods.

The newspaper said the state would save $270 million this year and $420 million in 1990 if the import-replacement program is carried out.

The report said the government wants local buyers to purchase domestic- made versions of the products, but it was not clear whether an actual import ban would be imposed. China has tried to reduce its trade deficit and promote domestic industries during the past several years by imposing restrictions on imports of both consumer items such as automobiles and electronic products and industrial equipment.

The State Statistical Bureau said the trade deficit last year was less than $4 billion, down from $12 billion in 1986.

The newspaper said imports of manufactured goods last year totaled $17 billion, about $200 million less than 1986.