Mobil Oil Corp. president William P. Tavoulareas yesterday appealed a federal judge's reversal of a jury's $2,050,000 libel judgment against The Washington Post in connection with a 1979 article about his business dealings.

Tavoulareas said initially he was not inclined to appeal last month's decision by U.S. District Judge Oliver Gasch to the U.S. Court of Appeals here. But he said that in the last few days he decided to appeal in an effort to change the standard by which so-called "public figures," such as Tavoulareas was determined to be in his suit against The Post, are judged in libel cases.

In order for public figures to be entitled to libel damages under the current standard, as spelled out in a 1964 Supreme Court decision (New York Times Co. v. Sullivan), they must prove that publications exhibited "actual malice" against them, knowingly printing false material or showing reckless disregard for the truth.

Gasch ruled that the disputed Nov. 30, 1979, article, written by reporter Patrick E. Tyler, fell "far short of being a model of fair, unbiased, investigative journalism." But the judge concluded, "There is no evidence in the record, however, to show that it contained knowing lies or statements made in reckless disregard of the truth."

In a four-page statement, Tavoulareas said "whatever the original merits of the strict holding on actual malice in the Sullivan case regarding public officials, I don't believe the Supreme Court ever intended or expected the rule to be extended in the ways and to the extent the lower courts have carried it."

Tavoulareas, who said he has "already spent in excess of $2 million" in legal fees on the case, declared he would "pursue this appeal vigorously and, if necessary, all the way to the Supreme Court."

Post Executive Editor Benjamin C. Bradlee said that "Judge Gasch reviewed the evidence in last summer's trial 'in the light most favorable' to Tavoulareas," according to the judge's opinion. "And he concluded that there was 'no evidence to support the jury's verdict.' As far as we are concerned, that's the bottom line."

The 1979 article detailed Tavoulareas' involvement in the 1974 creation of a London-based shipping firm, Atlas Maritime Co., that is run by his son Peter. Tavoulareas has claimed the article held him up to ridicule and embarrassed him.

In his statement yesterday, Tavoulareas said, "In recent days, I have received an outpouring of mail, telephone calls and face-to-face statements urging me to appeal. Many, who under Gasch's ruling would be 'public figures,' have impressed upon me the responsibility I now bear as perhaps the only person now in a position to challenge this unfair and unconstitutional interpretation of libel law.

"At the same time, almost every press person or media lawyer that I have met tried to discourage an appeal. I wonder why. Would an appeal be a further embarrassment? Do they fear a loss of power if I won an appeal?" Tavoulareas said he believed that if Gasch's ruling "stands unchanged," it would, in part, give "complete practical immunity from damages when the press libels loosely and broadly defined 'public figures' " and would erode "public confidence" in national leaders and the press.

"That Judge Gasch reversed the jury's verdict because he said I had failed to show malice in a legal sense in no way erases the moral malice exhibited by The Washington Post and its reporters' behavior," Tavoulareas said.