AFL-CIO's executive board is considering a proposal by one of its federal affiliates to ask the AFL-CIO's 14 million members to boycott U.S. savings bonds. A decision is expected today.

Small investors are the backbone of the payroll savings program. A massive boycott and cash-in by individual buyers could hit Uncle Sam hard in the pocketbook.

Kenneth T. Blaylock, president of the American Federation of Government Employees, asked the council to authorize the boycott to protest Carter administration wage and price policies. The controls are "voluntary" for most people. But President Carter has announced a limited 5.5 percent October federal-military pay raise despite data showing the average civil servant is due more than twice that amount to catch up with industry pay levels.

AFGE, the largest federal union and one of the biggest AFL-CIO affiliates, has already urged its members to cash in bonds they hold, and not to buy anymore. Union officials say government civilian employes buy about $1.1 billion worth of bonds each year.

If the union gets approval for a membership-wide boycott from the AFL-CIO-and it probably wouldn't ask unless it thought it would be granted - the people who are in charge of the savings bond program will have a rough sales season ahead of them.