This paper aims to analyze the personal and environmental factors that influence the perception of insecurity in the case of walking trips in Dakar (Senegal), according to the travel situation (daytime / night-time, inside / outside one's neighborhood). The empirical analysis is based on data from the household mobility survey carried out in 2015 (3,176 households and 13,415 individuals aged 11 years and over). Descriptive and multivariate statistical analyses (a multiple correspondence analysis and logit models) highlight significant differences in the perception of insecurity according to the travel situation (day / night; individuals' own neighborhood / elsewhere) and the characteristics of individuals, their household and residential neighborhood. The travel situation strongly influences the prevalence of the feeling of fear and has allowed us to identify a gradient in the perception of insecurity. Among the socio-demographic characteristics, gender plays a pre-eminent role and having previously been the victim of a robbery or assault while waiting for public transport increases the probability of feeling fear. The contextual determinants (public lighting, characteristics of sidewalks; social homogeneity, isolation, and dangerousness of one’s neighborhood) show that a degraded or insufficiently developed urban environment adversely affects urban dwellers’ feelings of insecurity. Economic resources, whether those of the individual or their household, play a less important role. Our results argue for greater consideration of the perception of insecurity when considering the mobility practices of urban dwellers in sub-Saharan Africa, especially with regard to pedestrian trips.