Ehud Ben-Mordechai was born on May 13, 1965 in Tel Aviv to American parents, Malka and Rabi. He was brought up and studied in Ramat Gan.
In June 1983 he was drafted into the IDF's Golani Brigade. He completed his compulsory service in August 1986 and joined the central branch of the Police in Tel Aviv. In June 1987 he married Lilli and in March 1991 their daughter Noa was born.
On July 3, 1991 Udi (Ehud) was killed during a terrorist attack on the Mt. Hermon outpost, where he was performing reserve duty. He was buried in the Kiryat Shaul Military Cemetery.