What actors and actresses appeared in Ano hi mita hana no namae wo bokutachi wa mada shiranai - 2013?

You're likely referring to the anime series "Ano Hi Mita Hana no Namae wo Bokutachi wa Mada Shiranai" (also known as "Anohana: The Flower We Saw That Day"). This is an anime, so it doesn't feature live-action actors. It features voice actors, and the main cast includes:

* Jinta Yadomi (Menma's childhood friend) - Aoi Yūki

* Menma (Jinta's childhood friend who passed away) - Ai Kayano

* Tsuruko "Tsuru" Koyama (Menma's best friend) - Haruka Tomatsu

* Anaru (Jinta's childhood friend) - Saori Hayami

* Yukiatsu "Yuki" Miyazoe (Jinta's childhood friend) - Takahiro Sakurai

* Poppo (Jinta's childhood friend) - Natsuki Hanae

There are also many supporting characters who are voiced by other actors. You can find a full list of voice actors on the anime's official website or on sites like MyAnimeList.