Yes. The Canon EOS 60D and T3i use the same hot shoe type, so a strobe that safely triggers on a 60D should also work on a T3i.

More generally, Canon EOS hot shoes are physically very consistent across bodies. If you only need a basic manual trigger through the center contact, hot shoes are largely standard across many camera brands as well. Advanced features such as E-TTL and high-speed sync depend on the extra contacts and camera/flash communication, which can vary by system and generation.

One caution: very old flashes can have high trigger voltages. Even though modern Canon DSLRs can tolerate fairly high sync voltage, some vintage flashes may still be risky. So if your strobe is modern and already works safely on the 60D, it should be fine on the T3i; if it’s an older flash, check its trigger voltage before mounting it directly on the camera.