The Fila Brasileiro is an excellent estate guardian and cattle dog. It does not hide its aversion to strangers, consequently these dogs are not disqualified from the show ring for showing aggression to the judge. Their faithfulness to family and friends is legendary, but this breed is not for everyone. The Fila needs a confident, experienced owner who can properly curb the breed's natural aversion towards strangers. Because of its aversion, it is not well suited to busy households which have many guests. Such aversion is instinctive in Filas, so much so that the Brazilian breed standard advises show judges not to touch the dog. However, the FCI standard allows for disqualification of very aggressive dogs. Few Filas will attack for no reason, but none will be friendly with strangers.

Filas love and bond strongly with their immediate families with an extreme loyalty and protectiveness. They live to protect their loved ones, including children and other pets. They do not readily accept strangers and need an extended introduction period to warm up to others they do not know. Some will never warm up to any stranger. Some bloodlines have less temperament than others and might accept a stranger if introduced properly by the owner, but it should never be assumed that every Fila can be trained to accept strangers. They are known to play very well with children and take a great deal of "abuse" from them, as long as they are family.