The first venture of Kishore Biyani was Pantaloons. Kishore Biyani, an Indian entrepreneur, is known for revolutionizing the retail sector in India. In the late 1990s, Biyani founded Pantaloons, which was initially a fashion retail outlet. This marked his entry into the business world and laid the foundation for his later ventures, including Big Bazaar, Central, and Future Capital Holdings. Therefore, among the given options, Pantaloons was his first venture.