Montgomery Ward & Co. said yesterday it plans to close its Gaithersburg store at the end of March.

Ward's cited economic conditions and its inability to realize a satisfactory return on investment in the store, which is located near the Montgomery Village complex off Interstate 270.

A spokesman for the nation's sixth largest chain said no plans have been made to close any of the other eight Montgomery Ward stores in the Washington area. The other Montgomery Ward stores here "are all doing well" and "no plans to close them should be inferred from the closing of the Gaithersburg store," the spokesman added.

Although officials said Montgomery Ward will attempt to transfer eligible employes to its eight remaining stores in the Washington area, the March 31 closing will eliminate another 230 retail jobs in the area. The Gaithersburg store employs 80 full-time and 150 part-time workers.

More than 1,200 employes will be out of work after today when the 13 Washington-area Memco stores close. The closing of the Woolco chain will eliminate another 1,200 or more retail jobs in the area.

"We have many experienced, capable employes in this store, which has made this a very difficult decision for the company," said Mal Pavik, district manager for Montgomery Ward.

Pavik said his company will work actively with other employers in the Washington market who may require the skills of employes at the Gaithersburg store.

The decision to close the Gaithersburg store came as a surprise to retail industry officials in the Washington area. Opened six years ago as the first full-line department store in that part of Montgomery County, the Ward's store was expected to draw heavily from the growing affluent population in the Montgomery Village area.

The store is located at Montgomery and Frederick avenues, only a short distance from Lakeforest Mall, one of the largest regional shopping centers in metropolitan Washington.

Montgomery Ward officials had hoped that the proximity of the Gaithersburg store to Lakeforest Mall, which opened later, would attract more customers. But free-standing department stores in suburban locations aren't enjoying the success that they had in the past, observed Leonard Kolodny, manager of the retail bureau of the Greater Washington Board of Trade.

A Montgomery Ward official conceded yesterday that demographics were a factor in the decison to close the Gaithersburg store, but he said it was "only one consideration."

The same official dismissed industry reports that Montgomery Ward, whose performance has slipped in recent years, is considering additional closings throughout the country. The Chicago-based retail chain, which is a subsidiary of Mobil Corp., closed two department stores and two Jefferson Ward discount units last year.

The 350-store chain reported a 6.2 percent gain in sales for December, but sales were off 1.9 percent over 11 months.