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Structure, magnetic, and transport properties of the compounds Bi0.5Ca0.5Mn1−xCrxO3 (BCMCO) with 0⩽x⩽0.15 have been experimentally investigated. The substitution of Cr3+ ion for Mn3+ ion suppresses the charge-ordering (CO) state obviously, leading to a gradual reduction of the CO transition temperature (TCO). In contrast, the antiferromagnetic (AF) ordering temperature is essentially unaffected until x=0.024. A spin-glasslike behavior appears above x=0.024 due to the competition between the antiferromagnetic and ferromagnetic correlations. The latter emerges and develops with the incorporation of Cr. The AF phase disappears completely for x⩾0.1, whereas the CO phase is still perceptible for x=0.15. A further analysis indicates that Cr doping produces a similar effect on TCO for the Bi-based and lanthanide-based manganites: TCO decreases at the same rate of ∼8 K for 1% Cr, despite the different initial values of TCO. A striking observation of the present work is that for the manganites, there exists a characteristic temperature 180 K, and the CO state will be unstable when TCO<180 K. As a result, a heavier Cr doping is required to completely destroy the CO phase with a higher TCO. For BCMCO, the critical Cr content is estimated to be about 0.2. Electrical study shows that the conduction of BCMCO proceeds via variable-range hopping of charge carriers, and a huge magnetoresistance can be produced by Cr doping.