Kinuta Park as one of the best hanami park in Tokyo
My recommendation is Kinuta Park in Setagaya-ku, Tokyo. You can visit there by bus from Futako Tamagawa station of Tokyu Den'en Toshi Line or Yoga Station of Tokyu Den'en Toshi Line, or Seijyo Gakuen Mae station of Odakyu Line. It is very big park with much of greenery atomsphere. The best season is hanami period as there are considerable amout of cherry blossom trees and they are weeping cherry blossom towards ground. You can do hanami party under cherry blossom tree shade. It is so impressive with Japanese beauty of cheery blossom. I always bring my foreign guests for hanami party and all of them are 100% sure to enjoy ! You may see the attached photo which I took with my guests a few years ago.