Walter Eugen Kolb (22 January 1902 - 20 September 1956) was a German politician of the Social Democratic Party (SPD) who served as Mayor of Frankfurt from 1946 until his death in 1956.

in 1923 Kolb was arrested by the French authorities who were occupying the Rhineland, during which time he completed his first state exams.

He opened a law firm in Bonn, where he defended political prisoners; he was arrested for these activities several times.

One of Kolb's most important tasks after the war was the reconstruction of Frankfurt, which had been damaged significantly by allied bombing.

In 1946, Kolb encouraged the intellectuals Max Horkheimer, Theodor W. Adorno and Friedrich Pollock, who had been living in exile in the USA, to return to Frankfurt.

In the municipal elections of 1956, held after Kolb's death, the SPD won 54.5% of the vote, the best result in their history.

The Walter Kolb Memorial Prize has been awarded by the Goethe University Frankfurt for outstanding dissertations since 1957.