Over 60% of the world population lives within a 150 km belt from the coastline. These territories that combine classic urban characteristics and natural features (coast, beaches, salt marshes, biodiversity reserves) are fragile but also attractive for residence, leisure and retirement. They are characterized by an unequal repartition of amenities, services, jobs as well as by uneven real estate prices. This geographical and social context raises the issue of inequality in the capability of using urban spaces, which can need a regulation from public authorities (ESCR Global Environmental Change Program, 2001). A growing attention is paid by geographical research to uneven distribution of environmental properties. We propose to analyze environmental and ecological inequalities in the specific context of urban coastal areas in order to determine the influence of the coast on the structuring of this type of territories. Environmental and ecological inequalities can be defined as observed and perceived differences, in the relation between humans and their living environment, which can discriminate individuals or groups of individuals under 4 categories: territorial inequalities that refer to differences in the quality of territories and the distribution of population groups; inequalities in access to urban and environmental amenities that refer to unequal opportunities of mobility in the city, of access to spaces and public goods, as well as possibilities of choice of residence places; inequalities in nuisances and hazards exposure; inequalities in the capacity of action and interpellation of public authorities for the transformation of living conditions. The aim of our study is to analyze through a quantitative analysis to what extent, coastal cities have specific socio-environmental characteristics compared to inland cities and to determine if those specificities may reinforce the socio-environmental inequalities in coastal territories. Focusing on French medium sized urban spaces (between 100 000 and 200 000 inhabitants) we offer a comparative analysis of the spatial distribution of socio-environmental characteristics between coastal and inland urban areas. Then, still relying on this definition and on these indicators, we will focus on coastal urban areas. Multivariate analysis of data show that cities are divided into two groups: coastal groups and continental ones. Coastal urban areas are defined by a more touristic profile. The population is older and lots of equipment is dedicated to this population. The building and development dynamic is strong. Among coastal cities, it is possible to define different geographical profiles whose characteristics can be analyzed in terms of socio-environmental inequalities. Inland urban areas are defined by a larger proportion of social, cultural and education equipment. The population is dominated by working population but the entrepreneurial dynamic is lower. The surface of agricultural land is higher and the use of green transportation is more common. Finally the risks exposure is lower. In a context of growing attractiveness, politic options can play a central part in limiting the development of inequalities and managing the consequences of the attraction of the coastal part of the city and the associated socio-environmental inequalities resulting from the competition between groups of population.