Receiving the prize near Berlin's iconic Brandenburg Gate watched by German Foreign Minister Guido Westerwelle, Ono, 80, said: "This prize is a message to me from you that what I've been doing was understood by you."
"Now is time for action and action is peace. Think peace, act peace, spread peace, and let's make it all together," she added.
The Tokyo-born artist - raised in both Japan and the United States in a well-off family of bankers - became a global icon when she married Lennon.
Since her Montreal honeymoon with the Beatles rocker, during which the couple called for peace from their marital bed, Ono has used her celebrity to raise awareness for causes.
She handed the €10,000 that comes with the Institute for Foreign Relations (IFA) award to Boniface Mwangi, who runs an organization
that helps young artists in Kenya.
In December, she won a separate German human rights prize for peace activism, as well as her more recent work championing equality for women and homosexuals.
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