I came to us in 2008 and approved asylum to leave in us. I apply for my wife to come to us and finally the document sent to embassy in Ethiopia. She went to embassy on the day of appointment with the relevant document and the visa consular officer denied her a visa. The reason he gave her is he don't convinced with the marriage. So what shall I do at this point.
Thanks

Common scam many use to get a green card. Because of that they have been cracking down on that for a LONG time... they make the rules... if they even suspect something isn't what is claimed they can reject it.

Having 6 kids with her that can be proven via DNA... is one way, but in any case, you have to prove she IS a real wife to you to their satisfaction. I'd start by asking them how you can prove it to their satisfaction.

You can appeal the decision. I assume you sponsored her based on your post.

Note that in order to overcome a negative decision you must have new or relevant information to include along with the original application. You should have received reasons for the decision, if not you may, and I would, request them. That way you will know what the reviewing officer based his decision on e.g. living arrangements, specific documents, misrepresentation, etc.

All the best.

You have 30 days to file an appeal, if pass the 30 days frame then you must re-file. The key is you two must be able to prove that marriage is bona fide. In this case, I would recommend having an experienced immigration attorney handle your case. Good luck.