The word “informal” was first used to describe economic activity that did not fit into the industrialised and western ways of working, and was mainly seen in developing economies. The employees and the enterprise are the two main vantage points from which it can be observed. It is characterised in the workplace as labour that is not governed by laws or regulations. Both in rural and urban areas, the labour force participation rate has gradually increased. However, the economy is not creating any formal jobs. India is facing a severe mismatch between the rate of employment growth and technological changes in output. The major aims of this chapter are to review the importance of informal sector workers in India and various problem faced by the workers, to critically analyse the working and employment status of informal workers, and to analytically review the socio-economic and occupational health implications of informal workers in India. To achieve these farmed objectives, various existing literature and relevant data has been sourced and reported to make a conclusion. Based on the critical analysis of various aspects of the informal workers, conclusions are made and few appropriate recommendations are given.