INDIANAPOLIS (AP) _ Eli Lilly & Co. said Tuesday its earnings rose 26 percent to a record $274 million for the second quarter, led by sales of the antidepressant drug Prozac and other pharmaceuticals.

For the three months ending June 30, earnings per share were 93 cents, compared with 75 cents on net income of $217 million during the same period in 1989. Sales rose 24 percent to a record $1.23 billion from $986.6 million during the second quarter last year.

Chairman Richard D. Wood said Lilly experienced sales growth in each of its operations.

''Sales increased in both international and domestic markets. Higher unit volume continued to be the main contributor to the quarter's results,'' Wood said. Operating costs grew slower than sales, he added.

Worldwide sales of pharmaceutical products ''were significantly higher than those of the second quarter of last year,'' Lilly said in a prepared statement. Besides Prozac, other pharmaceutical sales leaders included the drugs Axid, Ceclor, Dobutrex, Humatrope and Humulin, Lilly said.

Lilly also reported record results for the first six months of 1990. Net income increased 23 percent to $615 million, or $2.07 per share, on sales of $2.47 billion.