Not only is there indirect evidence that Mrs. Bennet knows but in chapter 2:

Mr. Bennet: Then my dear, you may have the advantage of your friend, and introduce Mr. Bingley to her.
Mrs. Bennet: Impossible, Mr. Bennett, impossible, when I am not acquainted with him myself; how can you be so teazing?

Also:

Mrs. Bennet: Well, how pleased I am! and it is such a good joke, too, that you should have gone this morning, and never said a word about it till now.

In my opinion, Mr. Bennet's teasing is so obvious and on-going, even the likes of Mrs. Bennett couldn't help but be aware of it. Mrs. Bennet doesn't seem to have the capacity to spar with her husband in either a joking or witty manner so I think ignoring is one way she copes with it. Also, Mrs. Bennet has a one track mind: doing whatever she feels she needs to do to put her daughters in the path of eligible men so they may marry and marry well. Often, when she is seriously trying to discuss things she sees as important in accomplishing her mission, Mr. Bennet resorts to teasing. But Mrs. Bennet is puffing on that track to her destination and refuses to let Mr. Bennet derail her. When she is in this mode and Mr. Bennet starts teasing, she stays on the topic and answers him as if the teasing remark/s had not been said. Just my humble opinion.