Blanche of Valois (baptised Marguerite; 1317–1348) was Queen of Germany and Bohemia by her marriage to King and later Holy Roman Emperor Charles IV.

The couple clashed with the Bohemian nobility who had gained strength because of King John's frequent trips abroad; despite this challenge, Blanche learned Czech and German, had a social life and would remain in Bohemia when Charles traveled abroad.

John put pressure on Blanche due to the birth of only a daughter, Margaret, and the absence of a living male child.

On 11 July 1346, Charles was elected king of Germany in opposition to Holy Roman Emperor Louis IV.

On 11 October 1347, Louis IV died suddenly and Charles gained wider recognition as king of Germany.

Seven years after the death of Blanche, Charles became emperor; he was eventually succeeded by his son Sigismund, whom he had with his fourth wife Elizabeth of Pomerania.