In an effort to counter President Carter's attack on the three-martini lunch, the National Restaurant Association today released a survey that it said puts to rest a number of myths about expense account meals.

The survey claims that the most popular expense account lunch consists of a hamburger, salad, french fries and coffee.

Of 10 beverages ordered at expense account meals, cocktails - which would include marinis - are ordered at only 3 per cent of the occasions, ranking higher only than beer, wine and other beverages, according to data supplied by chain restaurant eating out share trends (CREST).

Coffee the most popular beverage, is ordered at 27 per cent of such occassions followed by coft drinks (17 per cent), hot or iced tea (14.4 per cent) and milk (7 per cent).

As for main courses, the hamburger, regualr (14.4 per cent) and the hamburger, large 13.5 per cent) are followed by the other sandwich (12.6 per cent) in popularity, and clearly outdistance steak 2.7 per cent), roast or sliced beef (3.2 per cent) and other presumably more expensive entrees.

President Carter, in his attack on supposedly extravagant expense account meals which are deductible as business expenses, has painted an emotional picture that has no relation to fact, according to Victor Rossellini, president of the association which is meeting in New York.

He said the average expense account meal amounts to $3.93, which he said is in line with the average restaurant customer's check.

Rossellini, in a speech called Three-Martini Folly, painted his own picture of high unemployment and a depressed restaurant industry if the proposals that have been floated by the Carter administration to cut down expense account meal deductions are enacted.