A method for forming a brilliant coating film on a substrate, comprising the steps of: applying an aqueous first brilliant base coating composition containing a brilliant pigment to the substrate to form a first base coating at a first stage in a base coating zone; applying, successively to applying the aqueous first brilliant base coating composition, an aqueous second brilliant base coating composition containing a brilliant pigment to the first base coating formed in the step to form a second base coating at a second stage in the base coating zone without preheating the applied first base coating composition; applying a clear coating composition to the second base coating formed in the step to form a clear coating in a clear coating zone; and simultaneously heating the uncured coatings formed in the steps, and to cure the coatings, with the following proviso II: the proviso II of a condition (A-2) that the aqueous first brilliant base coating composition has a brilliant pigment mass concentration of 3 to 25 % and the aqueous second brilliant base coating composition has a brilliant pigment mass concentration of 7 to 30%, and a condition (B-2) that the ratio of the brilliant pigment mass concentration of the aqueous first brilliant base coating composition to the brilliant pigment mass concentration of the aqueous second brilliant base coating composition is 1/3.5 to 1/1.5; and with the following proviso III: the proviso III of a condition (A-3) that the aqueous first brilliant base coating composition comprises at least one organic solvent and water, and the mass ratio of the at least one organic solvent to the water is from 5/95 to 49/51, and a condition (B-3) that the at least organic solvent includes 40 to 100% by mass of a particular organic solvent, which is acetone, methyl alcohol, ethyl alcohol, or isopropyl alcohol, and the aqueous first base coating having a dry film thickness of 5 to 15 μm the aqueous second base coating having a dry film thickness of 2 to 8 μm the ratio of the dry film thickness of the first base coating to the dry film thickness of the second base coating being 1.5/1 to 5/1 and the clear coating film having a dry film thickness of 10 to 60 μm. applying an aqueous first brilliant base coating composition containing a brilliant pigment to the substrate to form a first base coating at a first stage in a base coating zone; applying, successively to applying the aqueous first brilliant base coating composition, an aqueous second brilliant base coating composition containing a brilliant pigment to the first base coating formed in the step to form a second base coating at a second stage in the base coating zone without preheating the applied first base coating composition; applying a clear coating composition to the second base coating formed in the step to form a clear coating in a clear coating zone; and simultaneously heating the uncured coatings formed in the steps, and to cure the coatings, the proviso II of a condition (A-2) that the aqueous first brilliant base coating composition has a brilliant pigment mass concentration of 3 to 25 % and the aqueous second brilliant base coating composition has a brilliant pigment mass concentration of 7 to 30%, and a condition (B-2) that the ratio of the brilliant pigment mass concentration of the aqueous first brilliant base coating composition to the brilliant pigment mass concentration of the aqueous second brilliant base coating composition is 1/3.5 to 1/1.5; and with the following proviso III: the proviso III of a condition (A-3) that the aqueous first brilliant base coating composition comprises at least one organic solvent and water, and the mass ratio of the at least one organic solvent to the water is from 5/95 to 49/51, and a condition (B-3) that the at least organic solvent includes 40 to 100% by mass of a particular organic solvent, which is acetone, methyl alcohol, ethyl alcohol, or isopropyl alcohol, and the aqueous first base coating having a dry film thickness of 5 to 15 μm the proviso III of a condition (A-3) that the aqueous first brilliant base coating composition comprises at least one organic solvent and water, and the mass ratio of the at least one organic solvent to the water is from 5/95 to 49/51, and a condition (B-3) that the at least organic solvent includes 40 to 100% by mass of a particular organic solvent, which is acetone, methyl alcohol, ethyl alcohol, or isopropyl alcohol, and the aqueous first base coating having a dry film thickness of 5 to 15 μm the aqueous second base coating having a dry film thickness of 2 to 8 μm the ratio of the dry film thickness of the first base coating to the dry film thickness of the second base coating being 1.5/1 to 5/1 and the clear coating film having a dry film thickness of 10 to 60 μm.