The abnormal expression of long noncoding RNAs (lncRNAs) is closely associated with human cancers. As one special group of lncRNAs, natural antisense transcripts (NATs) can be transcribed from both DNA strands at the same locus but in the opposite direction from the gene transcript. Their expression levels are altered in many cancers, but their roles are poorly understood. We strove to find NATs involved in human non-small-cell lung cancer (NSCLC) and to reveal their mechanism of action in cancer. We analysed the NATs in NSCLC from the TCGA database by circlncRNAnet. One NAT, family with sequence similarity 83 member A antisense RNA 1 (FAM83A-AS1), was found to be markedly upregulated and positively correlated with its cognate sense counterpart, FAM83A, in NSCLC. Moreover, overexpression of FAM83A-AS1 increased FAM38A protein levels and induced ERK1/2 phosphorylation downstream of FAM83A in cells. Finally, overexpression of FAM83A-AS1 promoted LUAD cell proliferation and invasion. In summary, lncRNA FAM83A-AS1 promotes LUAD by increasing FAM83A expression.