Why are male dogs always after my sterilized female dog?

I have 4 males and 2 females all are entire it can be a bit of a nightmare when the girls are in season, other than that they all get on very well. And I have never had an accidental matting. But if I was you I would get the male done now and the female done after her 1st season. As you say you don't want to breed so you don't need the hassle of all those hormones :) hope this helps

Lots of things can be causing this. Humping behavior is not always sexual in nature, many times it is simply an over-stimulated male dog due to a multitude of reasons.

Dog parks aren't always the best place to take your dog as many loose dogs don't have very good doggy manners and their owners don't seem to care.

Your dog may be giving off signals to the other dogs that cause this. Watch her body language and see if you can figure out what triggers the males actions.

Could she possibly have a vaginal infection which could give of scents that stimulate an intact male.

You might have a chat with the owners of the dogs that are bothering her and ask them what they are seeing. There is always a reason for this, not necessarily sexual.

I'd suggest because they know a spayed female is probably not going to see them off like an entire b itch will, unless she's actually in season!! It's a pain in the neck when males do this, or rather, when the b itch won't see them off - nothing works better in switching off a male, than being told to shove off, by the female.

I guess your only choice is to protect her, if she won't do it herself.

Add Just another thought on this one - have you noticed any 'fishy' smell coming from her rear end? I've found in the past that if any of mine has an anal gland problem, it did attract my males. Much as they didn't go so far as to attempt to mount! It might be worth having your vet manually empty these glands, just in case there impaction/infection going on. I've also noticed in the past, that some bitches do seem to give off a smell, even if spayed, at about the time they would have been in season. However, if your b itch was done so long ago, I doubt this is what's going on. Just people with hooligan dogs in the park ...... ask them to get their dogs under control, might help!

It is very likely she has a UTI & BLOOD in her urine, crystals in her urine or has problems with kidney or bladder stones or some other type of vaginal infection. Most males can't tell the difference (re blood scent in that area). Take her to a vet!

This is not related to sterile or fixed. This is a matter of dominance and lack of proper social and play skills.