It is the oldest religion in the world still practiced today that uses permanent structures. The Aboriginals are of course over here breaking the graph re: oldest religion at all, and many Native American and First Nations religions are "they're old, we've been doing this for as long as we've been a nation and that's all we're telling you," so it's difficult to say how many of them predate Judaism. Probably at least some, probably not all.
Judaism's oldest antecedents--that's to say, the point where it began breaking off from the rest of Canaanite religion but still looked closer to that than it did to modern Judaism--date to about 2000-1500 BCE. The earliest Hindu literature is just a hair younger--1500-1000 BCE. Note that just as Judaism was a baby at this point, this is only the earliest bit of Hinduism--most Vedic literature was written in the 800s BCE, and Krishna doesn't appear until sometime between 800 and 600 BCE.
Jainism dates to "probably the 800s BCE with a small margin for error to the younger end."
Zoroastrianism and Confucianism both date to the 500s BCE. The Buddha is born sometime between 563 and 400 BCE.
The Second Temple period begins in 515 BCE. At some point shortly before this, the written Torah was redacted into its final form.
Taoism dates to the 300s BCE.
The first Christian Council dates to sometime between 50 and 63 CE.
The Temple was destroyed, giving rise to rabbinic Judaism, in 70 CE.
Christianity in the most basic form it exists today dates to the Council of Nicea in 325 CE.
Muhammad lived between 570 and 632 CE. The Qur'an was written by one of his followers beginning with his death in 632 CE.
The entirety of both the Greek and Roman religions fits within the lifespan of Judaism. The beginnings of the ancient Egyptian religion date to the prehistoric era, but the version of it we'd recognize from school, with Isis and Osiris and so on? Yeah, that only dates to about the 2600s BCE. It predated Judaism, but Judaism's lifespan from "we wrote down the version of Torah we still read" to, well, now, is roughly equal to the entire existence of the ancient Egyptian religion as we'd recognize it.
We refuse to die. And that pisses off a whole lot of people.