Research data and original images are provided in support of the publication “Porous AlGaN-based ultraviolet distributed Bragg reflectors”. The dataset includes the sample structures and the electrochemical setup as illustrated in Figure 1. The Atomic Force Microscopy images of the sample A and B were included before and after the electrochemical etching as presented in Figure 2. Cross sectional scanning electron microscope images of sample A and B are included as presented in Figure 3 and 4. The original reflectivity spectra data (.xls) used to plot the graphs in Figure 5 are also provided.