Introduction: In Senegal, breast cancer is the second most common cancer in women after cervical cancer.1 It is responsible for a high mortality rate of around 70% after five years,2 as in many other developing countries. Mammography plays an important role in the screening and diagnosis of breast diseases. The unfavourable conditions in our regions are at the origin of the inaccessibility and unavailability of this diagnostic tool. Objectives: The objective of our study was to evaluate the availability, accessibility and use of mammography in the diagnosis of breast diseases in the Senology Unit of the University Hospital Aristide Le Dantec in Dakar. Materials and methods: This was a descriptive and analytical cross-sectional study of 120 patients followed at the Senology Unit of the Aristide Le Dantec University Hospital in Dakar, during the period from 1 January 2010 to 31 December 2014. The parameters studied were: the socio-economic profile of women, the geographical distribution of functional mammography centres, the time taken to perform mammography, its cost, its quality and its contribution to diagnosis. Results: In our study, the majority of patientes lived in the suburbs of Dakar (67.5%). The average age was 44.2 years. More than half (54.2%) had no regular source of income. The rate of use of mammography was 8.9%. The average cost was 48,944 FCFA. The average time taken to carry out a mammogram after it was prescribed was 28.8 days. In 76.6% of cases, mammography was performed for diagnostic purposes. In no case was an additional examination performed. As regards the quality of the mammographic examination, in 17.5% of cases the usual marking was not respected and the transparency of the images was not optimal in 26.6% of cases. The validity criteria were not met in 18.3% of the results and the American College of Radiology (ACR) BIRADS classification was used in 95 patients (79.2%). Payment before the examination was carried out was in cash in the majority of cases (70.8%). However, the difference in cost was significant according to the type of imaging centre (p = 0.015). Conclusion: Mammography was characterised by the unavailability of centres, a fairly long time to carry out the examination and a lower quality of the examinations.