Farm Sink Drain Installation
That does not appear to be correctly installed, it should lie flush with or below the sink surface.

These strainer assemblies commonly come with 2 ring-shaped washers; one rubber and one hard plastic or fiber. Both should be placed on the underside of the sink between the strainer mounting hardware and bottom sink surface. Neither are for "sealing" purposes. The rubber one is a cushion and the plastic/fiber one is a friction ring. 

Make sure that there is no gasket of any sort between the upper strainer lip and the sink (it sure looks like there is...). The only thing between the strainer lip and the sink should be plumber's putty, and any excess putty squeezes out when the strainer is tightened (until flush with or below the sink surface) to the sink.

The only other possibilities are that the strainer has not been tightened completely down, or the sink (or strainer) is defective.