This might be why dogs hate the mailman.

Giovanni Baena of Dallas, Texas, caught a US Postal Service carrier, who is not being identified, pepper-spraying his three dogs on his home surveillance camera on Dec. 13, WFAA reported.

Baena says he became concerned when his dogs, who were barking loudly, suddenly became quiet.

“They were barking a little more aggressively, and then they just stop,” Baena said. “I walked outside and caught a whiff, and it smelled like pepper spray. Then I saw it here on the fence and a spatter on the wood.”

Baena claims the dogs were behind a 6-foot-tall fence and even though they bark, they weren’t putting anyone in danger.

“There’s no reason for them to just come by and spray them,” Baena said. “Uncalled for, very unnecessary, and unprofessional.”

Footage from the incident shows the mailman putting letters in a mailbox before walking off and spraying the dogs for no apparent reason.

Luckily, Baena’s dogs were unharmed. He filed a complaint with his local post office.

The USPS did not immediately respond to The Post’s request for comment, but it gave this statement to WFAA: “The Postal Service strives to always provide the best possible service to our valued customers. It is disappointing when, on rare occurrences, we fall short of that goal. Local management was made aware of this video shortly after the customer brought it to their attention and it has been addressed with the Letter Carrier.

“This is clearly unacceptable behavior and does not reflect the efforts of the thousands of professional, dedicated Letter Carriers in our workforce. We sincerely apologize to the customer,” the statement continued.

The USPS declined to say whether the employee had been disciplined or fired, saying it does not discuss “personnel actions or matters that may impact personal privacy.”