Delta Air Lines reported record fourth-quarter earnings of $103.3 million, or $2.11 a share, up from $58.8 million, or $1.21 a share, for the year-ago quarter ending June 30.

Fourth quarter revenues totaled $1.9 billion, up from $1.6 billion a year ago.Delta also reported annual earnings for the period ending June 30 of $306.8 million, or $6.30 a share, up from $263.8 million, or $5.90 a share, for the previous year.

Revenues increased to $6.9 billion in 1988, a 30 percent increase from $5.3 billion a year ago.

"Strong revenue gains resulting from traffic growth and improved passenger mile yield were the principal ingredients in Delta's record earnings," said Thomas J. Roeck, Delta's chief financial officer.

"The major elements in achieving these quarterly results were a 20 percent growth in revenue made possible by a 13 percent growth in passenger miles and an 8 percent jump in passenger mile yield," Roeck said. "Also, the price of fuel rose only 1 percent over the average for the 1987 quarter."

During the year, passenger revenue miles increased 28 percent to 49 billion from 38.4 billion.

Results for the 12-month period reflected the acquisition of Western Air Lines by Delta in December 1986.

The board of directors also declared a cash dividend of 30 cents per share, payable Sept. 1 to the stockholders of record on Aug. 10.