- In SQLDeveloper browse
Tools --> Preferences
, as shown in below image. - In the Preferences options
expand Database --> select Advanced --> under "Tnsnames Directory" --> Browse the directory
where tnsnames.ora present. - Then click on Ok,
as shown in below diagram.
tnsnames.ora available atDrive:\oracle\product\10x.x.x\client_x\NETWORK\ADMIN
Now you can connect via the TNSnames options.