Pretty damn close. In fact, The 400m wide asteroid called 2005 YU55 will get closer to our home planet than the Moon itself: 324,600km. That’s 0.85 the distance from our silver satellite. So no, it will not kill us. But it will get close enough to get uncomfortable.
According to NASA, the “trajectory of asteroid 2005 YU55 is well understood”, so there’s no dangers whatsoever. Its gravitational influence will not affect anything in our planet, so don’t expect volcanoes to go off, tectonic plates to sink into magma or tides getting New York under the Atlantic ocean. It will just pass by as scientist observe it using the Goldstone and Arecibo antennas, so expect some asteroid porn in the coming days.