Yuki to Watashi (Heidi Version) sung by Kazuko Sugiyama.

Heidi, Girl of the Alps (アルプスの少女ハイジ Arupusu no Shōjo Haiji) is a 1974 Japanese anime series by Zuiyo Eizo.

The soundtracks were composed by Takeo Watanabe.

This is from Disc 1 of the Limited Edition Official Soundtrack.

Lyrics Japanese:

まっしろな 子山羊
なまえは ユキ
いつかしら はじめて
あなたと であったのは
そうね
あの 泉のほとり
冷たい水を いっしょにのんだ日

Lyrics transliteration:

Masshirona koyagi
Namae ha yuki
Itsuka shira hajimete
Anata to deatta no ha
Sou ne
Ano izumi no hotori
Tsumetai mizu wo issho ni nonda hi