Rendering problem sawtooth

I get this surface from baking grasshopper component. It looks fine, but when I rendering it, I get this sawtooth image. how to get a smooth rendering image?
This is the first time I met this.

Hi,

A wild guess: might he object be very large and/or very far away from the origin?
If so try to scale it down and place it close the the world origin (0,0,0)

Or you could export just the object in a file and post it here. Without the file it is hard to track down the cause.

-Willem

Thanks Willem!
I just tried persepective (before it was in parallel viewpoint), then it becomes fine.
yes, it is far from the origin. I would like try your way when I want the rendering in parallel viewpoint.