Dengue is a viral disease caused by any of the four distinct dengue virus (DENV) serotypes that circulate in many parts of the world. DENV now co-circulates with Zika and Chikungunya viruses (ZIKV and CHIKV) in many regions of the Americas. Having this in mind, plus the fact that DENV clinical diagnosis persists as a difficult task, due to the similarity in symptoms, as well as false-positive results by the cross-reactivity of the IgG and IgM against these three viruses, correct identification of DENV at an early stage of the disease is essential to minimise transmission and prevent potentially devastating sequelae. Here, by phage display, we isolate specific peptides for dengue virus NS1 protein. The specificity of the linear peptides as diagnostic tools for DENV NS1 protein in sera samples was investigated, and the selected peptides showed the ability to recognise DENV, and no cross-reactivity was shown. Moreover, in silico analysis was performed to assess the possible binding modes of these peptides to DENV-NS1, using a molecular docking approach. These peptides are suitable for use in an ELISA assay for dengue virus detection in human serum and the possibility to adapt these peptides to PoC platforms.