竹やぶの一軒屋にお祖母ちゃんと二人暮らしのミミ子。ある日、おばあちゃんが法事で旅行に出かけてしまいミミ子はひとりぼっちになる。小学生ながらしっかり者のミミ子が買い物から帰ってくると小さな子パンダのパンちゃんが庭にいた。さらにその親のパパンダも現れる。ミミ子に父親がいないことを知ったパパンダは自分が父親代わりになると言い、ミミ子はパンちゃんの母親になると決める。こうして２頭はそのままミミ子と暮らすことになり、奇妙で楽しい新生活が始まった。

One day, Papa Panda and his son, Pandy, make a daring escape from a zoo in hopes of finding themselves a nice and cozy home. A charming little house near the bamboo thicket attracts their attention, and they decide to drop in for a friendly visit. It is here that they find a sweet young girl, Pamela, who is house-sitting while her grandmother is away.
In talking with Pamela, they learn that she has no parents, so Papa Panda, feeling sorry for her, volunteers to be her new Daddy. In return Pamela offers to be Pandys new mother. From this day forward, they all live together as one big happy family, each day bringing a new and exciting adventure.