A material injection scheduling method for producing a precursor having a concentration gradient using an apparatus for producing a precursor having a concentration gradient mixing materials of a first feed tank and a second feed tank with each other in advance in a mixer and injecting the mixed material into a reactor, the method comprising: (a) a step of calculating a feed flow rate of the mixer by dividing a sum of a total amount of the material of the first feed tank and a total amount of the material of the second feed tank by a total process time (Tr); (b) a step of calculating a feed flow rate of the material of the first feed tank during the total process time (Tr) in a pattern in which it gradually decreases for each time using Equation 2 below: a flow rate (FQ1t) of the first feed tank for each time = 2 x (total amount of material of the first feed tank - amount of material of the first feed tank stored in the mixer in advance - amount of material of the first feed tank injected in advance) / (time required for feeding entire materials of the first feed tank - time already taken for injection into the first feed tank) (c) a step of calculating an injection amount by creating an Equation representing a linear shown in Fig. 8 and substituting each time values making a difference in the feed flow rate of the material of the first feed tank constant; (d) a step of correcting the feed flow rate of the material of the first feed tank by calculating a difference between the injection amount and the flow rate of the first feed tank for each time calculated in step (b), and the values of the difference are arranged to time in reverse order to be subtracted from the injection amount calculated in step (c); and (e) a step of calculating a feed flow rate of the material of the second feed tank by subtracting the feed flow rate of the material of the first feed tank corrected in the step (d) from the feed flow rate of the mixer. (a) a step of calculating a feed flow rate of the mixer by dividing a sum of a total amount of the material of the first feed tank and a total amount of the material of the second feed tank by a total process time (Tr); (b) a step of calculating a feed flow rate of the material of the first feed tank during the total process time (Tr) in a pattern in which it gradually decreases for each time using Equation 2 below: a flow rate (FQ1t) of the first feed tank for each time = 2 x (total amount of material of the first feed tank - amount of material of the first feed tank stored in the mixer in advance - amount of material of the first feed tank injected in advance) / (time required for feeding entire materials of the first feed tank - time already taken for injection into the first feed tank) (c) a step of calculating an injection amount by creating an Equation representing a linear shown in Fig. 8 and substituting each time values making a difference in the feed flow rate of the material of the first feed tank constant; (d) a step of correcting the feed flow rate of the material of the first feed tank by calculating a difference between the injection amount and the flow rate of the first feed tank for each time calculated in step (b), and the values of the difference are arranged to time in reverse order to be subtracted from the injection amount calculated in step (c); and (e) a step of calculating a feed flow rate of the material of the second feed tank by subtracting the feed flow rate of the material of the first feed tank corrected in the step (d) from the feed flow rate of the mixer.