The main purpose of this paper has been to formulate a clear idea about the socio-economic and demographic background characteristics of informal and formal sector workers. A comparison between the two groups was attempted. Particular attention has been directed to certain characteristics that are assumed to be the potential micro determinants for joining the informal labor market in Egypt. These include gender, age, marital status, education, principal work status, and some other socio-demographic characteristics. A ‘Chi-squared' test and ‘Discriminant Function Analysis' were applied as a statistical assessment in differentiating between the groups. Years spent in education made the greatest contribution in differentiating between the two groups: This followed by principal work status, gender, and age. It can be also concluded from the Discriminant Function Analysis that migration status and level of income are more strongly associated with informal sector workers. ‘The remaining variables by contrast are more strongly associated with workers within the formal labor markets.