Harold House, Liverpool's Jewish community centre, faces temporary closure unless it can raise £100,000.
The centre is due to move into the new King David schools complex under construction on a neighbouring site and IS scheduled to open in September 2011.
But Harold House chief executive Stephen Simpson warned that the centre cannot continue until then without a cash influx.
"I have to find the funds to keep us going. We are facing a very challenging scenario to find benefactors who will come forward to help us with the work we do looking after the education and well-being of Jewish children," he said.
"I have done everything I can since I arrived 18 months ago to secure funding. Two benefactors came forward and have helped us in the interim but we cannot keep going back to the same people. Now I have to appeal to the wider community to give us help as soon as possible."
He feared that if Harold House had to close for a year or more, "we would lose the impetus that going into the new school would bring".
Harold House is used by up to 40 children in after-school clubs and numerous adult groups across the community. Organisations including JNF have offices in the building.
"We know the community in Liverpool is declining," Mr Simpson added. "But it is vital that we continue the work we do without any break, so that however many Jewish children there might be at King David, we are there to provide a foothold in the community."