Bethlehem Steel Corp. reported yesterday its second-quarter earnings fell $4 million between 1984 and 1985, from $24 million to $20 million, and the company does not expect to make a profit this year. For the first half of 1985, net losses also increased to $42 million, from $31 million the year before.

Eastman Kodak Co. said its profit fell 28 percent in the second fiscal quarter, mainly because of the strong dollar and depressed selling prices for chemicals.

*Bethlehem Steel Corp. sales for the second quarter were $1.3 billion, compared with sales of $1.5 billion for the same period last year. Sales for the first half of this year totaled $2.5 billion, compared with sales of $2.8 billion for the first half of 1984.

"The steel market remains flat. The continuing heavy influx of foreign steel, a seasonal downturn in certain markets and cautious customer inventory policies make any improvement in third-quarter shipments unlikely," Chairman Donald H. Trautlein said in the earnings report.

"Steel prices have declined during the year and continue to be weak," he said.

*Eastman Kodak Co., based in Rochester, N.Y., said net earnings of $164.3 million in the company's quarter ended June 16 were down 28 percent from $229.3 million in 1984's second quarter. Earnings per share were 72 cents, compared with 92 cents last year.

Worldwide sales for the world's largest photographic company were $2.46 billion, 4 percent lower than the $2.56 billion posted in the second quarter of 1984.

Earnings from operations were $287.4 million, 30 percent less than the $409.8 million recorded a year earlier.

"The adverse impact of the overvalued U.S. dollar, coupled with depressed selling prices in the chemicals industry, which were due in large part to the dollar's strength, more than account for the difference between 1984 earnings and those reported thus far in 1985," Colby H. Chandler, the chairman and chief executive officer, and Kay R. Whitmore, the president, said in a statement.

Sales for the first half of the year were $4.58 billion.