Many thinner that are used by the automotive paint, they are divided into two. Those are: Thinner NC or DUCO (Nitrocellulose) and Thinner PU (Polyurethane). Kinds of thinner can be used to soluble all kinds of paint. Although, those paint have different womb from other thinner. The aim of this research is to know the quality of painting result, and the effect of using the thinner Polyurethane (PU) and Nitrocellulose (NC) toward the quality of painting result. Kind of this research is experiment. Meanwhile, Thinner NC or DUCO (Nitrocellulose) and Thinner PU (Polyurethane) are used in this research. By mixing the variant of thinner Polyurethane (PU) and Nitrocellulose (NC) in the paint of Polyurethane (PU) and Nitrocellulose (NC). The comparison in each the thinner and the paint encompass 1:1, 1:1.3, 1:1.5. Examination of the gloss of paint result uses glossmeter. The result of this research can be found that the thinner of Polyurethane (Pu) in the paint of Polyurethane (Pu) by comparing the mixture 1:1,3 can get the best result. Moreover, it can get the highest gloss in the number of 87.4 GU. Meanwhile, the thinner of Nitrocellulose (NC) is mixed with the paint of Nitrocellulose (NC) by comparing 1:1,5 can get the highest gloss in the rate of 81.4 GU. This research finds Droplet like rough surface paint that caused by the thick mixture thus it will generate low gloss level. Then, Droplet is such as the pinhole formed, it is caused by the kind paint of NC which runs drying quickly, by mixed the thinner of PU which is later run drying. Key words: Thinner, Mixing variant, glossmeter.