Dear Mohanty,
1. Create the Asset master data in the system via LSMW or BDC or anyothe means.
2. Seondly perfom AS91 by uploading the APC value, asset balance and accumulated depreciation, note this should be done only in AA side, the same should not reflect in FI side.
3. Perform OASV transaction to perform the same in FI side.
Also check this link for more details.
Fixed Assets - Data Migration from Legacy system
Lokesh M S