We presented the rapid diagnostic test for dengue infection based on light spectrum of human blood. The transmission spectra of dengue infected whole blood samples have been recorded in ultra violet to near infrared range (400–800 nm) of about 30 conformed infected patients and compared to normal blood samples. Transmission spectra of dengue infected blood illustrate a strong band from 400–600 nm with prominant peaks at 540 and 580 nm, where is in case of normal blood below 600 nm, total absorption has been observed. These prominent peaks from 400–600 nm are characteristics of cells damage and dangue virus antibodies immunoglobulin G (IgG) and immunoglobulin M (IgM) produced against dengue antigen. The presented diagnostic method is non invasive, cost effective, easy and fast screening technique for dengue infected patients. (© 2012 by Astro Ltd., Published exclusively by WILEY‐VCH Verlag GmbH & Co. KGaA) (© 2011 by Astro Ltd., Published exclusively by WILEY‐VCH Verlag GmbH & Co. KGaA)