Long noncoding RNA (lncRNA) LUADT1 is a known oncogenic lncRNA in lung cancer. This study aimed to explore the roles of LUADT1 in melanoma. Sixty pairs of melanoma and nontumor tissues were obtained from 60 melanoma patients (37 men and 23 women, 38-68 years, 52.1 ± 4.9 years) at the First Affiliated Hospital of Zhejiang University School of Medicine. Gene expression was analyzed by quantitative polymerase chain reaction and western blot. Cell transfections were performed to analyze gene expression. We found that LUADT1 was upregulated in melanoma and high levels of LUADT1 predicted poor survival. RNA interaction prediction showed that LUADT1 can form base pairing with miR-28-5p. In melanoma cells, LUADT1 overexpression mediated the upregulated Ras-related protein Rap-1b (RAP1B). Cell proliferation assay showed that LUADT1 and RAP1B overexpression mediated the increased proliferation rate of melanoma cells. In addition, miR-28-5p overexpression played opposite roles attenuating the effects of LUADT1 overexpression on both RAP1B expression and cancer cell proliferation. LUADT1 in melanoma and may sponge miR-28-5p to upregulate RAP1B, thereby promoting cancer cell proliferation.