Are you referring to a Ginseng Ficus by any chance? If so, it is not uncommon for Ficus to drop their leaves when their environment changes. A move to a new location can trigger this. Have you moved it recently or perhaps just acquired it. Has it been subjected to a period with insufficient water? Have you recently fertilized it and if so in what concentration? You have not really given us much to go on, more information may help. Pictures certainly would not hurt either.