The idea of mashiach (messiah) is an ancient one in Judaism
The Jewish idea of mashiach is a great human leader like King David, not a savior
There is much speculation about when the mashiach will come
The Bible identifies several tasks that the mashiach will accomplish
Jews do not believe in Jesus because he did not accomplish these tasks
It is written that:
Before the time of the mashiach, there shall be war and suffering (Ezekiel 38:16)
And:
The mashiach will bring about the political and spiritual redemption of the Jewish people by bringing us back to Israel and restoring Jerusalem (Isaiah 11:11-12; Jeremiah 23:8; 30:3; Hosea 3:4-5). He will establish a government in Israel that will be the center of all world government, both for Jews and gentiles (Isaiah 2:2-4; 11:10; 42:1). He will rebuild the Temple and re-establish its worship (Jeremiah 33:18). He will restore the religious court system of Israel and establish Jewish law as the law of the land (Jeremiah 33:15)
Jews do not believe that Jesus was the mashiach. Assuming that he existed, and assuming that the Christian scriptures are accurate in describing him (both matters that are debatable from the Jewish perspective), he simply did not fulfill the mission of the mashiach as it is described in the biblical passages cited above. Jesus did not do any of the things that the scriptures said the messiah would do.
On the contrary, another Jew born about a century later came far closer to fulfilling the messianic ideal than Jesus did. His name was Shimeon ben Kosiba, known as Bar Kokhba (son of a star), and he was a charismatic, brilliant, but brutal warlord. Rabbi Akiba, one of the greatest scholars in Jewish history, believed that Bar Kokhba was the mashiach. Bar Kokhba fought a war against the Roman Empire, catching the Tenth Legion by surprise and retaking Jerusalem. He resumed sacrifices at the site of the Temple and made plans to rebuild the Temple. He established a provisional government and began to issue coins in its name. This is what the Jewish people were looking for in a mashiach; Jesus clearly does not fit into this mold. Ultimately, however, the Roman Empire crushed his revolt and killed Bar Kokhba. After his death, all acknowledged that he was not the mashiach.
Throughout Jewish history, there have been many people who have claimed to be the mashiach, or whose followers have claimed that they were the mashiach: Shimeon Bar Kokhba, Shabbatai Tzvi, Jesus, and many others too numerous to name. Leo Rosten reports some very entertaining accounts under the entry for meshiekh in The New Joys of Yiddish. But all of these people died without fulfilling the mission of the mashiach; therefore, none of them were the mashiach. The mashiach and the Olam Ha-Ba lie in the future, not in the past.
Source: http://www.jewfaq.org/m/mashiach.htm