Ukrainian miners in the coal-rich Donetsk Basin are threatening another strike this summer if the Soviet government does not meet their demands.

More than half a million miners at Donetsk and other mines around the Soviet Union are demanding more local control of their industry, freedom to retain hard currency earnings and better supplies of consumer goods.The Donetsk miners will hold a meeting on June 11 to decide whether to begin another summer of strikes.

Last summer, the Donetsk miners held a three-week strike that brought the Soviet coal industry to a standstill.

Meanwhile, a major international trade fair will be hosted at Donetsk this summer, in an effort to attract Western technology needed to modernize the mines.

According to one U.S. entrepreneur contacted at his headquarters office, the desperate miners are making efforts to obtain equipment through barter arrangements involving coal, lumber and possibly other products.

The U.S. businessman, who sells cranes, bulldozers and other construction goods, said he was working on a deal with labor bosses in which he would be paid in coal. It's unclear exactly how the deal would work, or under what authority the mine workers would be able to trade the coal.

The businessman said he would try to sell the barter coal in the international market, at below-market prices, if necessary.

The trade show Coal '90, scheduled to run in Donetsk from Aug. 26 through Sept. 4, is being dubbed as a major opportunity for foreign exporters of coal technology to sell to the Donetskmines, which have some hard currency to buy Western equipment.

"Significant hard currency expenditures are expected to be allocated at Coal '90 from both the Ministry of Coal and the Donetsk miners," said Gerard Seeber, first commercial secretary for the Australian Trade Commission in Moscow.

The Soviet coal industry is in dire need of modernization along Western lines, and there are signs that the hard currency being allocated to pay for this technology is in great demand by Soviet mines.

Recent Soviet statistics reveal what a crisis the Soviet coal industry is in and why it needs to import technology from the West.

Soviet coal output in 1989 fell by 32 million metric tons, or 4.1 percent, of which strikes accounted for 7 million tons of the loss.

In the first quarter of 1990, according to a Pravda report last month, coal extraction is down 6 percent this year revealing the industry's worsening situation.

Mr. Seeber, the Australian trade representative in Moscow, said six Australian companies are jockeying for space at the fair and that the West Germans will be there "in a big way."

The Australian companies planning to sell to the Soviets in late summer include Amdel Ltd., based in Frewville, which plans to sell coal slurry analyzer systems, programmable mineral analyzers and interface gauges.

Banlaw Proprietary Ltd., based in Caves Beach, hopes to market its automatic refueling and lubrication equipment.

BMCH Proprietary Ltd., based in Gordon, will try to sell its bulk materials handling systems to the Soviet coal industry.

Mineral Control Instrumentation Ltd., of Indooroopilly, is marketing its on-line coal sampling and analysis systems.

Last March, Ruhrkohle, the big West German coal mining group, and the Soviet Ministry of Coal Industry discussed the possibilities for cooperation in mining.

Also, Kloeckner of West Germany signed a contract with a Soviet coal association called Kargormash to assist in raising the technical standards and efficiency of Soviet coal machinery, according to Interflo, a Soviet trade news monitor.

The South Koreans have also staked their claim to the soviet coal market. Hyundai and Daesung Consolidated Mining Co. are planning to form a joint- venture coal mine in Partizansk near the Far Eastern Port of Nahodka to produce 300,000 to 500,000 tons of bituminous coal a year.

Though European and Asian companies are making headway into the Soviet coal market, there are no indications here that U.S. companies are ready to jump into a market considered a mixture of risks and opportunities.

"It was our decision not to get involved," said Bob Hess, international sales manager for Dresser Industries' Jeffrey Division, which makes underground coal mining equipment.

He said that the last time the show was held, in 1983, there were "no serious sales prospects." Also, by and large, U.S. underground equipment isn't suitable for use in the Soviet Union because the mines there are much deeper than in the United States.

Dresser Industries has sold oil field equipment to the Soviets for many years, so political considerations have not been a factor in the company's decision, he said.

Chas Bruniany, international sales manager for mining equipment for Joy Technologies, Pittsburgh, also noted that European and Australian mining equipment is more compatible with conditions in the Soviet coal industry.

''I may go, but we won't have a stand. I've been invited to present a paper," he said.

Ann Grosier, a vice president of the American Mining Congress, Washington, D.C., said that U.S. equipment companies were represented in mining trade meetings held earlier this month in Beijing and in Chile.

Tim Sansbury in Washington and Sam Glasser in New York contributed to this story.