Electronic Journal of Differential Equations, Vol. 2015 (2015), No. 261, pp. 1-14. Title: Well-posedness and blowup criterion of generalized porous medium equation in Besov spaces Authors: Xuhuan Zhou (Zhejiang Univ., Hangzhou, China) Weiliang Xiao (Nanjing Univ. of Finance and Econ., Nanjing, China) Taotao Zheng (Zhejiang Univ. of Science and Tech., Hangzhou, China) Abstract: We study the generalized porous medium equation of the form $u_t+\nu \Lambda^{\beta}u=\nabla\cdot(u\nabla Pu)$ where P is an abstract operator. We obtain the local well-posedness in Besov spaces for large initial data, and show the solution becomes global if the initial data is small. Also, we prove a blowup criterion for the solution. Submitted June 25, 2015. Published October 07, 2015. Math Subject Classifications: 35K15, 35K55, 35Q35, 76S05. Key Words: Generalized porous medium equation; well-posedness; blowup criterion; Besov spaces.