Thrips palmi is one of the most serious insect pests, causing adverse effects on vegetable production. In China, the insect pest was first discovered in Guangdong Province in the 1970s and has gradually become a major insect pest of vegetables, especially solar greenhouse vegetables. For example, in 1993 solanaceous fruit vegetables such as eggplant, green pepper and potato were damaged seriously by T. palmi, and the damage rate was about 90% in the Hangzhou district. In recent years, with the development of solar greenhouse vegetables in northern China, T. palmi has survived through the winter in solar greenhouses and damaged vegetables throughout the year, so controlling these insect pests has become more difficult. Physical control is an important control technique within integrated pest management (IPM), and the color plate trap is one of the most important methods of physical control. The color plate trap can not only reduce the number of T. palmi insects effectively, but can also forecast the occurrence of the insect pests in the field, so this method plays an important role in the IPM of T. palmi. The selectivity of T. palmi to colors in the field has been reported to show significant variation. To discover the photosensitivity of the insect pest, we studied the phototactic and photophobic behavior of T. palmi female adults in response to spectral sensitivity and light intensity by behavior method in the laboratory. The results showed that the phototactic response of T. palmi female adults to monochromatic light at 14 different wavelengths within a 340-605 nm range occurred in a curve with multiple peaks. The primary peak, representing the highest phototactic response (34.96%), occurred at a wavelength of 483 nm (blue), the secondary peak at 498-524 nm (green), and the remainder at 562-582 nm (green) and 340 nm (ultra-violet). The photophobic response occurred in a curve with three peaks: one peak at 380 nm (ultra-violet) represented the highest photophobic response rate (18.08%), and the other two peaks at 605 nm (orange) and 420 nm (violet). Under the stimulus of monochromatic light-at which the T. palmi showed high phototactic response rates (340 nm, 483 nm, 524 nm, 582 nm, 380 nm, 605 nm) and high photophobic response rates (380 nm, 605 nm)-and white light, the phototactic response rate of T. palmi female adults increased with increasing light intensity, while the photophobic response rate decreased. The response rate of T. palmi female adults could be detected at the lowest intensity but not at the height of the strongest intensity. Therefore, in T. palmi female adults, both the spectrum and intensity of light stimulus resulted in phototactic and photophobic responses under monochromatic light conditions, and the level of response was proportional to the wavelength. The results obtained provided a theoretical basis for further investigation and applications as well as for the evaluation of scientific light traps used to monitor and control T. palmi.