Data on demographic, social and behavioural characteristics of female sex workers in greater Cairo are very scarce. A cross-sectional study was conducted with 431 randomly selected sex workers after mapping of sites where they gather. Data collection was performed by direct interviewing using a questionnaire sheet covering sociodemographic data and sexual history with paying and non-paying partners. More than one half of participants (52.7%) were aged < 30 years. Only 39.3% were exclusively working as sex workers while the rest had other jobs beside sex work. Almost 70% were responsible for dependants. The age of first selling sex was < 15 years for 4.7% of the women and 15–25 years for 58.7%. Unwanted pregnancies were experienced by 36.2% and 34.8% had had an abortion. Many participants had ever been arrested by the police (71.2%). The study has provided some useful background data for further studies in this very sensitive area of research.