Cheating emerges early in development and has significant moral development implications. This research investigated whether cheating in 5- to 6-year-olds reflects strategic decision-making or impulsivity. Through four preregistered studies, we systematically manipulated adult presence and observability across multiple conditions using a challenging math test paradigm. Study 1 (N = 150) demonstrated that children cheated least when an adult was visible (6%), moderately when only audible (20%), and the most when neither visible nor audible (48%). Study 2 (N = 150) revealed that this effect was driven by whether the adult could readily observe children's cheating, rather than by her mere presence. Studies 3 and 4 (N = 50 each) further showed that children strategically adjusted their behavior based on how readily their cheating could be detected. These findings challenge the notion that preschoolers' deceit is primarily driven by impulsivity, suggesting that at age 5-6, children can make sophisticated deceptive decisions based on social context and circumstances.