My ex wife is trying to add or change the surname of my son to her boyfriends surname. She has asked me personally and I refused to allow anything of the sort. She does not allow me contact with my son this is no fault of mine. I have not seen him for two years. Is it possible in any way for her to add or change my sons surname without my permission

Yes and no. She cannot get a legal name change without your consent. However, she can use any name she wants to for him as long as there is no intent to defraud. So. For example, if she tells the school that he will be using John Smith instead of John Jones, she can.

Why haven't you seen your son? Is there a visitation order in place?

my ex wife is trying to add or change the surname of my son to her boyfriends surname. she has asked me personally and i refused to allow anything of the sort. she does not allow me contact with my son this is no fault of mine. i hav not seen him for two years. Is it possible in any way for her to add or change my sons surname without my permission

Why haven't you taken her back to court the first time she refused you visitation ? That should have been 2 years ago. ( yes its your fault ). As far as a legal name change without you knowing that shouldn't happen. But go into court right away as soon as they open and file. If you don't have custody orders get them if you do file for contempt of court and excersize your rights. Don't just wait on your ex to do something.