Introduction: In the last year, Peru experienced a climatic phenomenon called Niño Costero. This generated rains, alluviums and floods affecting thousands of people and causing the declaration of health emergency in the country. In spite of the occurrence of similar phenomena in the affected areas, these are usually occupied as places to live. Objective: To identify the characteristics of risk’s perception during floods in people who live in vulnerable zones. Method: A qualitative empirical research was developed in the year 2017. The semi-structured interview technique was conducted in nine people living in four districts of Lima (Peru) whom were susceptible to flooding. The information collected was analyzed with the support of Atlas.ti v. 7.0., software for the qualitative data analysis, using elements of the Grounded Theory to develop the coding and categorization processes. Results: It was found that the participants do not elaborate a perception of risk before the threat of floods. They envisage the floods as a threat when experience their consequences. Conclusions: It is necessary to implement interdisciplinary researches that allow to generate evidence for the development of interventions aimed to the creation of a risk’s perception that will be coherent with the consequences and the impact of floods.