<p>This article aims to analyze the perception of the effects of climate change and its relationship with food security held by peasant producers in the South Pacific coastal region of Mexico. The methodology used has a mixed approach, the method is deductive, with the application of ethnographic research; to collect and analyze the data, a structured survey was applied in 225 Rural Production Units (RPUs) randomly distributed in three municipalities of Oaxaca and three of Guerrero. The results show that 97.78% have perceived that there is a climate change and it has a direct impact on food security because it was determined that 52.59% of the population reported that they have experienced a strong concern about the lack of food. Regarding the characterization of the RPUs, 8% still live inside wooden walls, 12% do not have potable water in their homes. The analysis of the information leads to conclude that food security in the study region is a multidimensional problem: food shortage in the municipalities under study is highly marked; climate change contributes to the worsening of this problem and it is necessary to design local adaptation strategies.</p>