Disclosed is an economic method for concentrating virus and detecting virus, such that virus in a sample solution having low virus concentration can be concentrated with high efficiency within a short time. Particularly, the method comprising the steps of: (A) adding Concanavalin A (Con A) to a sample solution containing a virus, and reacting the added Concanavalin A with the virus in the sample solution to form a virus-Concanavalin A conjugate; and (B) separating the virus-Concanavalin A conjugate from the sample solution.