The zombie drama is known for killing off series regulars, including Shane (Jon Bernthal) and Dale (Jeffrey DeMunn).
"People would be dying left and right in this kind of situation, and to not portray that in the way we're doing, it would be completely inaccurate," Kirkman told Entertainment Weekly.
He continued: "Every season of The Walking Dead is going to have major deaths. There are going to be characters that you've fallen in love with that will be taken away from you horribly. And you're going to be upset about it.
"But hopefully the story is engaging enough that you want to know what happens next and you want to stick around for the next character to die."
Back in March, Kirkman claimed that The Walking Dead will "always... be a bloodbath", while showrunner Glen Mazzara has hinted that there are "certainly deaths coming throughout the [third] season".
The series returns to FX in the UK and AMC in the US in October.