Although many organizations strive for radical or disruptive new ideas, many fall short of their goals. We propose that a primary reason for this failure is rooted in the individuals responsible for innovation: while they seek novel ideas, they prefer familiar ones. While prior research shows that individuals are biased against ideas with high objective novelty, it has overlooked the role of subjective novelty, i.e., the extent to which an idea is novel or unfamiliar to an individual idea evaluator. In this paper, we investigate how such subjective familiarity with an idea shapes idea evaluation in innovation. Drawing on research from psychology and marketing on the mere exposure effect, we argue that familiarity with an idea positively affects the evaluation’s outcome. We present two field studies and one laboratory study that support our hypothesis. This study contributes to the understanding of cognitive biases that affect innovation processes.