Tsukubashu is an anthology of renga (linked verse) poems collected under Imperial command in the period of the Northern and Southern Courts. It consists 20 volumes. It includes 2190 poems. Such composition of anthology follows the segmentation of Chokusen wakashu (anthology of Japanese poetry compiled by Imperial command).
This anthology was compiled by Yoshimoto NIJO in cooperation with a priest Gusai, completed in 1356 and designated as a quasi-imperial anthology in September 3 1357, therefore it became the first quasi-imperial anthology of renga in Japan. Completion of the renga anthology and designation of quasi-imperial anthology were realized with the great help of Doyo SASAKI, so many of the contributors were samurai families such as Takauji ASHIKAGA, Yoshiakira ASHIKAGA, and Doyo SASAKI, as well as Imperial families and court nobles. The anthology also includes ancient renga, so it shows the changes of renga. Compiling this renga anthology contributed to independence of renga from waka to flourish as an unique field of culture. 450 contributors to this anthology were known by name, most of them lived in and after the Kamakura Period.