Animation Source Forums

I have always believed that Scar is Nalas father.

My theory:

As cubs, Scar and Sarafina were friends. Feeling rejected and unfairly treated, Scar souhgt comfort and friendship in kind, shy Sarafina. I believe they could have mated as teenagers or young adults, with Nala as a result. I think that as Scar became more obsessed with power and more consumed with hate and darkness, Sarafina realized he was no longer the lion she once knew, and decided to break off contact. I think she would have been pregnant at this point, but chose not to tell Nala who her father was. And I doubt Scar would care.. (Yes, he would have needed an heir when he became king after killing Mufasa, but I doubt he would have chosen a female cub.)

I know Nala does not look like Scar, but let`s face it: She`s almost a copy of Sarafina. There is nothing about her looks or personality that could betray who her father is. Disney really didn`t bother thinking about that when they designed her, Nalas father was not important to the story. Even her mother was only given one line.

So yeah, that`s my theory.

I didn't vote. I think Nala's father was just a rogue. Simple as that.

Personally, I just think Disney was just too lazy to give her a history.

In groups like this the leader is the one who has the offspring, so scar is out of the question. And as a matter of fact I do believe it's Mufasa. Simba:"You know, your starting to sound like my father." Nala: "Good, at least one of us does."

http://www.youtube.com/watch?v=K5apnJcWoTU

Realistically it would be Mufasa; leaders of a pride are usually the ones to mate, as stated by MB.
But I personally think it's Scar, and I agree with Solle's theory