Gwen's naive nature is toned down in Ben 10: Alien Force; she is now more analytical than before. Gwen is a quick thinker and an instinctive person. At times she trusts others too quickly, and that may be a disadvantage or even injure her, like in Too Hot to Handle. She can handle dangerous situations, despite their often unfavorable conditions. An example of this being when her magical powers were drained and Charmcaster hit her with a bolt of magical energy; she immediately reversed the spell and, though she had no power left, she was able to hold herself.

Gwen is at times shown to be very concerned with the well-being of things around her, such as her surroundings, the people around her, and those she cares about. She is very strong (physically and mentally) and well mannered, despite her inflating sarcasm and ego at certain times. Gwen is a very caring, compassionate person, as shown by her acceptance of Kevin's past and recent actions, as well as her statements that she does not care about Kevin's appearance.