Ultraviolet A (UVA) radiation is capable of inducing various types of physiological effects related to all macromolecules in insects. However, the molecular mechanisms of insect responses to UVA radiation are still poorly understood. Transcriptional regulation of the expression of UVA-responsive genes is a crucial part of insect responses to UVA radiation. This research used the model insect Drosophila melanogaster to test its transcriptional response to UVA radiation via RNA sequencing, and systematically analyzed the head gene-expression profiles between different time points (0, 0.5, and 1.0 h). In all, 1,678 differentially-expressed (DE) genes were detected via pairwise comparisons among three different RNA-Seq libraries. Most DE genes, down-regulated continually or at the end point, were classified into cluster (1) of significant model profiles. Furthermore, combined with KEGG/pathways and Gene ontology enrichment analysis, DE genes greatly related to stress and defense responses, metabolic process, and enriched in signaling pathways responding to UVA radiation. A subset of differentially-expressed genes were selected to verify the RNA-Seq results through quantitative real-time PCR; the results of quantitative real-time PCR analyses strongly correlated with the RNA-Seq data. The results provided the extensive genetic components and possible mechanisms for insect resistance/adaptation to UVA radiation.