In a method for producing a biochip comprising a large number of spots based on captures, the spots are arranged on a base plate 10 by supplying, onto the base plate 10, a plurality of types of the captures to be used to specifically react with a specimen in order to obtain information on a structure or a function of the specimen, an immobilization-reinforcing solution 16 is supplied onto the base plate 10 (first supply step). Subsequently, a sample 14, which is obtained in a sample preparation step, is supplied onto the immobilization-reinforcing solution 16 having been supplied onto the base plate 10 to produce the biochip thereby (second supply step).