Global warming presents a threat for human and nature systems. For a few decades, sustainable food consumption behaviors have been considered remarkable to protect environmental sources. Changes in food consumption behaviors can benefit in improving environmental quality. While consumers are trying to reduce their environmental impact, it is needed to study what consumers think about the environmental impact of their consumption preferences. Earlier studies reported that sustainable conditions can bias judgments, since when an unsustainable plus a sustainable condition is thought as less environmentally impactful than the sustainable condition alone called "negative footprint illusion". In line with this, the current study aimed to examine negative footprint perceptual biases regarding sustainable food consumption. A within-subjects design was used with a total of 165 pre-service teachers studying at the department of science education in a mid-sized university in Turkey. Data were collected through a series of scales developed by Gorissen and Weijters (2016). The scales include three-meal menu food types including 'standard menu condition', 'sustainable-addition condition', and 'unsustainable-addition condition'. Participants were asked to evaluate the environmental impact of these menu conditions independently. The results of the study indicated that the participants believed that 'sustainable-addition condition' has a lower environmental impact than 'standard menu condition', even though 'sustainable-addition condition' indicates higher environmental impact--indicating a negative footprint illusion. It can be concluded that pre-service science teachers have perceptual biases related to sustainable food consumption even when they have enough knowledge related to environmental issues.