Boxer stud...

Sheesh, where to start....well first of all your dog is a puppy!  I would not even begin to consider breeding a male until he was at least 2 years old, provided he had all the health certifications and clearances and the level of training, titles, and competition applicable.

 I think this is a bad idea for many reasons, but not the least of which is that both of these breeds have some very serious genetic conditions that could pass to the puppies.  If neither dog has been tested for heart, hip, or eye problems (Google CERF, PennHip, OFA - Orthopedic Foundation for Animals), then you would not want to breed.  Also, who are the people you plan to give these puppies to?  Most people who are knowledgeable will want those tests, will likely want a purebred, and not a mix (there are lots of this type mix in shelters), and will not buy from someone whose dogs are neither shown, worked, or tested.  So, that leaves people who have little knowledge - is that where you would want your puppies to go?  A reputable breeder guarantees puppies for life - is the owner of the female, or are you, prepared to take those pups back if an owner is no longer able to care for them?  Breeding is a huge undertaking that usually costs more than it makes, and can be fraught with heartbreak - don't enter it lightly.  If you have a Boxer that comes from a reputable breeder (visit www.wonderpuppy.net and read their articles on that) and you want to breed him, join you local Boxer club (find it at www.akc.org) and go to shows, talk to knowledgeable people, and get really educated.  I think you'll find that there is more to this than sperm;-)))

 I will warn you that this is a forum dedicated to the health, wellness and advancement of dogs. The members do their best to educate people about the right way to care for dogs.  Breeding is a very sensitive issue.

That said I am very glad that you came here to ask this questions.  You will get very good information, take it seriously.

Both of these breeds have a long list of genetic health problems and if you were to seriously consider breeding them, AFTER BOTH DOG ARE 2, a lot of testing needs to take place.  Breeding either of these breeds without the testing is flat out irresponsible and creating problems.

Another question many will have is why you would essentially breed mutts?  Since good breeding is to advance the breed, intentionally mixing breeds is questionable.

There are absolutely NO pluses to intentionally breeding a boxer with a rottweiler.  If you want this combination, check your local animal rescue.  The fact that you are even asking the question suggests you should make an appointment to have your boxer spayed as soon as possible.

Air, good advice you've gotten and I agree.  Please do more research on both these breeds and also on responsible pet ownership.  We aren't trying to come down hard on you but as Karen said we are very passionate about being responsible dog owners.  Many here are involved in shelters, rescues, etc and see first hand the suffering and often death that comes with litters that are not well planned.  The puppies you bring into the world are truly your responsibility and that carries on long past the time you sell or give them away.