Problem encountered with Hard Disk

I was having trouble transferring data from one disk drive to another one. Midway upon the process of copying the data, an error interrupted that shows that my disk drive is having a bad sector and needs to be replaced or it might crash the system fully.
I tried again to transfer the data, I already restarted my computer but still the same error appears. I can't just leave it or make the drive to trash since I have important data there and I should save those data. I need help what should I do?
