The present research examines how creative process engagement (information gathering, idea generation, idea evaluation, and idea pitch) influences the affective states of positive affect (PA) and negative affect (NA). Drawing from motivation theory and research, we proposed that creative process behaviors that are more autonomous and less constrained will increase positive affect. Additionally, creative process behaviors that are more likely to be perceived as making negative goal progress are expected to result in higher levels of negative affect. We also examine boundary conditions of these effects including task-relevant knowledge, perceived performance, and baseline affect. Results from two studies confirm that idea generation, which is considered an autonomous activity, increases PA levels. This effect holds true across varying starting affect levels (excited, calm, and neutral). Moreover, results confirm that information search, which may be perceived as making negative goal progress, increases NA levels and PA levels decrease when task-relevant knowledge is low. The effects of idea evaluation and idea pitch on PA and NA are mixed across the two studies. The implications of these findings for understanding how the creative process impacts affect are discussed.