A vehicle body rear part structure includes a rear frame and a beam member. The rear frame has: a first inner bead, a first outer bead, a second inner bead, and a second outer bead. The first inner bead and the first outer bead are formed on an inner wall and an outer wall, respectively, in a region close to the beam member. The second inner bead and the second outer bead are formed on the inner wall and the outer wall, respectively, in a region that is separated to a vehicle body frontward direction from the first beads. The first outer bead is formed to have a higher fragility than the first inner bead.