The present invention provides a therapeutic agent for sepsis and/or septic shock and a method for screening for the therapeutic agent. The present invention relates to a therapeutic agent for sepsis and/or septic shock comprising an Arid5A inhibitor as an active ingredient. The present invention also relates to a method for screening for a candidate substance useful for the treatment of sepsis and/or septic shock, the method comprising: (a) determining an effect of test agents on the expression and/or function of Arid5A and (b) selecting the agents that decrease the expression and/or function of Arid5A as compared to the absence of the test agents.
