Halyomorpha halys (Stal), brown marmorated stink bug, is an invasive insect native to Asia that was accidently introduced into the United States. The species is a polyphagous pest that has caused serious economic injury to specialty and row crops in the mid-Atlantic region. Growers have targeted H. halys with broad-spectrum materials by increasing the number of and decreasing the interval between insecticide applications. While it is known that adults reliably respond to semiochemical cues, much less is known about the response of H. halys to visual stimuli. Field observations suggest that H. halys adults respond to light-based stimuli, with large aggregations of adults documented at outdoor light sources and captured in commercial blacklight traps. Therefore, we conducted a series of studies aimed at identifying optimal wavelengths and intensities of light attractive to H. halys adults. We found that intensity and wavelength of light affected H. halys response in the laboratory and field. In the laboratory, H. halys demonstrated positive phototactic responses to full-spectrum and wavelength-restricted stimuli at a range of intensities, though the levels of stimulus acceptance and attraction, respectively, changed according to intensity. The species is most attracted to white, blue and black (ultraviolet) wavelength-restricted stimuli in the laboratory and field. In the field, traps baited with blue light sources were less attractive to non-target insect species, but white light sources were more attractive to H. halys indicating that these two light sources may be good candidates for inclusion in light-based monitoring traps.