Australian supermarket and the retailing industry have a large participation in the economy of the country, where Woolworths and Coles are playing the role of duopolist. Both the companies have 80 percentage shares in the Australian economy. Apart from this, Wesfarmers is also playing a leading role in the country. This paper would shed the lights on the competitive strategy of Coles and Woolworths and also find the superiority of the firms in the competitive market. In this context, the business strategy and sustainability would also be described in this report.