A search for pair-produced bottom-like quarks in pp collisions at s=7TeV is conducted with the CMS experiment at the LHC. The decay b′→tW is considered in this search. The b′b¯′→tW−t¯W+ process can be identified by the distinctive signature of trileptons and same-sign dileptons. With a data sample corresponding to an integrated luminosity of 34 pb−1, no excess above the standard model background predictions is observed and a b′ quark with a mass between 255 and 361 GeV/c2 is excluded at the 95% confidence level.