As far as i know, they believe in Jesus and they accept him as Gods prophet. Just like Mohammed, Abraham, David etc. But the only distinct difference is that a muslim doesnt accept (nor believe) Jesus as the son of God. Therefore there is no Holy Trinity for them. They believe in Mary as being Jesus mother and she was also a virgin even after Jesus was born. Because Quran explains this birth very clearly.
So Muslims believe in Jesus very much. They just dont believe Jesus as the Son of God