The association marks Myntra's focus on establishing itself as the fashion brand for young India, the company said in a statement.
Launched in December 2012, Roadster is Myntra's in-house brand and has become one of the top selling brands on the website within a span of 15 months.
"Being the preferred fashion destination in the country, we constantly aim to resonate fashion and lifestyle in the hearts and minds of the youth of the country," Myntra Chief Marketing Officer Vikas Ahuja said.
Private brands play a significant role in this and in creating differentiation, choice and value for shoppers and Ranveer's power-packed and unconventional persona makes him the ideal choice for Roadster, he added.
Ranveer said: "Roadster is a brand I took a liking to instantly, the clothes are wonderful and are more than real value for the price point they are pitched.
"I subscribe to its philosophy of not being bound to any societal norms and Im really looking forward to doing some great work with Roadster as we continue ahead on the journey."
With over 650 products to choose from, Roadster offers denim products for both men and women, priced between Rs 300 - Rs 3,799.