Temperature is one of the most important abiotic factors affecting the physiology of ectotherms. Small ectotherms like insects rely on behavioral thermoregulation to maintain their body temperature within permissive range. The plasticity of preferred body temperature (Tp) contributes to an organism’s adaptive capacity to environmental changes. It also plays a substantial role in the establishment of invasive species. Here we studied the Tp plasticity of a major pest, the fruit fly Drosophila suzukii. A high Tp plasticity allows for more precise behavioral thermoregulation, decreasing the selection pressure on thermal tolerance. We hypothesized that larvae are less plastic than adult because they are constrained by the fruit selected by the mother. Furthermore, we tested whether the endosymbiont Wolbachia played a role in the level of plasticity of Tp. We measured the response of Tp to developmental temperature using a thermal gradient apparatus in a controlled laboratory environment. We assessed the effect of variables such as developmental stage, age, sex, reproductive status, and the presence of Wolbachia (developmental plasticity). We followed the flies for several generations to question a transgenerational effect on Tp. All studied variables affected D. suzukii’s Tp, suggesting a high plasticity. The developmental temperature influenced the mean Tp of adults, but not larvae, highlighting the importance of the mother’s temperature choice for its progeny. Females preferred higher temperatures than males, maybe to accelerate egg maturation. Wolbachia infected individuals had lower Tp than uninfected flies. The high plasticity of D. suzukii’s Tp could have contributed to its invasion success worlwide.