The amin purposes of this study were: (*) to characterise the traveller's perception of the subway 's olfactory environment and to study the annoyance toward the commuters. (*) to study the impact of individual factors such as age, sex, social condition and contextual ones such as the physical characteristics of the subway station (noise , temperature , light, design). (*) to compare the objective olfactory dimension of each subway station and the subjective evaluation by the commuters. (*) to evaluate the attitudes and the representations toward the subway itself, the comfort and the effects of the pollution on health. // A questionnaire has been filled out by five hundred representative commuters with regard to age , sex, social condition and to travelling frequency, in five different subway stations whith specific architectural and physical dimensions (noise , temperature, light...). We found that the cummuters experience the Parisian subway odour as a specific one. This specific smell in the subway results mainly from underground smells, human smells as well as odours coming from the material and cleaning products. These odours are usually welcomed by the travellers who associate them to cleanless and who find them rather reassuring and healthy. On the opposite, the three other kinds of odours, are very negatively perceived. We also found that individual factors such as age, sex or social condition have to be taken into account. The specificity of the subway station is also an important element: the olfactory perception and the annoyance do not strictly match the objective olfactory measurement. The other characteristics of the subway stations such as noise, light or temperature have also an impact on the odour's evaluation. Most of travellers associate bad smells to air pollution and to negative effects on human health; the more the people are sensitive to the pernicious influence of odors on human health, the more they evaluate negatively the olfactory environment . The image of the subway, people have in mind and the supposed effects of the pollution on health, seem to be very important factors to understand the annoyance due to odours in the Parisian subway.