A crisis occurs when the financial instability is up to a certain degree． As the important growth point of global economic development，emerging markets suffered from the heavy blow of the financial crisis． Thus，it is imperative to study the financial stability of emerging markets． This paper mainly discusses the financial stability of the major stocks of BＲIC countries ( China，Ｒussia，India，Brazil) ，the representatives of the emerging markets． Different from the traditional methods in this field，this paper focuses on the influence of systemic shock on normal and extreme markets respectively． First，aquantile regression model is used to test the financial stability of the BＲICs． Then a variable coefficient quantile model is proposed to study the timevarying trend of the impact that systematic shock has imposed on their financial stability． Also，a time-varying analysis is conducted subsequently． The empirical result shows that each of the BＲICs has a certain degree of financial instability． China and Brazil suffers more severely from the systematic shock at the 5 percentages compared with India and Ｒussia recently．