River flow is one of the important mechanism for seed transport and secondary dispersal of riverine plants species. Physical modification of stream channel and land cover change in watershed alters hydrological river flow and affect the dispersal of riverine plants in urban streams. We surveyed the transport of riverine plant seed during the flood event in two urban streams with different channel shape and land cover characteristics. We sampled transported seeds in channelized (Komagome river) and restored (Kido river) urban streams during the typhoon-induced flood in September 2018. Three seed traps were set up in each stream and we collected seed samples from river water in every six hours for three days. Collected seeds were sieved into different size class and visually identified with a microscope. We compared 1) different temporal pattern by seed weight, 2) diversity and abundance of seeds, and 3) relative proportion of secondary dispersal through comparison with standing vegetation in both sites. By understanding the relationship between flood and seed transport, our results will provide essential information to suggest practical guidelines of the urban stream management.