Legacy effects is a long-term effect across years. The legacy effect of herbivory is critical to change resource allocation pattern of plants in the following year, which in turn affects performance of focal plants. However, such long-term effect on perennial plants across years has received little appreciation. We conducted an herbivore-inoculation experiment using tall goldenrod and its dominant herbivores, lacebug and aphid in 2013 -2015 at a common garden in Shiga. This experiment contrasted the effects of two, fully crossed treatments; herbivory in the first (2013) and the following (2014) year, in either aphid or lacebug-inoculation, and undamaged treatment. We examined flower numbers and seed-ovule ratios in the following year as reproductive outputs.　First-year lacebug herbivory did not affect flower numbers and seed-ovule ratios. When lacebug herbivory was repeated in the following year, only flower numbers were decreased. On the other hand, first-year aphid herbivory did not affect flower numbers, but decreased the seed-ovule ratios. Although this negative effect was canceled when aphid herbivory was repeated in the following year, plants produced still few seeds due to reduced flowers. Our results highlight the importance of legacy effects on plant reproduction across years.