Abstract Exploring factors that influence desire for food and underlying mechanisms is important for preventing unhealthy eating behavior. From the mental simulation perspective, the current research investigates the effects of perceived spatial proximity of food on desire and the underlying mechanism. The authors propose that perceived spatial proximity negatively affects individuals’ desire through mental simulation. Limiting an individual’s perceptual resource (mouths) impedes mental simulation, and thus decreases the effect of perceived spatial proximity on desire. To test the above hypotheses, two experiments were conducted. The first experiment was conducted to test the effect of perceived spatial proximity on desire and the mediating role of mental simulation. This experiment was a one-factor (perceived spatial proximity: near vs. far) between-subjects design, and 95 college students participated in the experiment. The participants were randomly assigned into two groups (near vs. far). The stimulus was a print advertisement of a piece of cake. The perceived spatial proximity was manipulated as follows: The participants were told that the cake advertisement was from a store either near or far from their university. After viewing the advertisement, the participants indicated their desire and mental simulation on scales. The results of this experiment revealed that the participants in the near group reported a higher level of mental simulation and desire than those in a far group. Further analysis revealed that the mental simulation mediates the effect of perceived spatial proximity on desire. The second experiment was conducted to test the change of the effect of perceived spatial proximity on desire after limiting the individuals’ perceptual resource (mouths). In this experiment, the stimulus was an advertisement of an apple, and the perceived spatial proximity was manipulated by visually depicting the apple either near or far in the advertisement. This experiment was a 2 (perceived spatial proximity: near vs. far)ⅹ2 (perceptual resource limitation: limited vs. unlimited) between-subjects design. A total of 116 recruited college students participated in the experiment and were randomly grouped into four. To limit the participants’ mouths, they were asked to chew gum while viewing the advertisement. After viewing the advertisement, they reported their desire to eat the apple. The results showed that the mouth limitation decreased the desire through mental simulation for both the near and far groups, but the decrease effect was more significant for the near group than for the far group. The nearer an individual perceives the spatial proximity is, the more tempting the food is, and mental simulation mediates the relationship between spatial proximity and desire. Taking measures to limit the perceptual resources used when simulating mentally, the effect of spatial proximity on desire decreases. Theoretically, the current research is the first investigation to explore the effect of perceived spatial proximity on desire for food, and thus expands the scope of studies on eating behavior. Practically, the current findings provide insights into the manipulation of individuals’ desire for food. Key words desire for consumption, mental simulation, perceived spatial proximity