Who laughs last, laughs best

In English: Who laughs last, laughs best.-- A person who does his best is the one who will get the greatest satisfaction in the end. or: Don't express your joy, or triumph, too soon!

In German: Wer zuletzt lacht, lacht am besten.

In Spanish: El que ríe último, ríe mejor (same as in English)

In Portuguese: O último a rir, ri melhor.

In Russian: Смеётся тот, кто смеётся последний - absolutely similar to English