Chalcone and chromene motifs are synthetic or naturally occurring scaffolds with significant cytotoxic profile. Two types of novel regioisomeric chromene-chalcone hybrids, namely 1-(6-chloro or 6-methoxy-2H-chromen-3-yl)-3-phenylprop-2-en-1-one (Type A) and 3-(6-chloro or 6-methoxy-2H-chromen-3-yl)-1-phenylprop-2-en-1-one (Type B), both with different substituents on the phenyl ring attached to propenone linkage, have been evaluated for their cytotoxic activity against breast cancer cell lines (MCF-7 and MDA-MB-231). The results indicate that type A of chromene-chalcones demonstrated better cytotoxic profile than type B especially in MDA-MB-231 cell line. In addition, the growth inhibitory activity of most of the target compounds is higher than Etoposide as a reference drug. QSAR analysis of these novel compounds demonstrated that topological and geometrical parameters are among the important descriptors that influence the cytotoxic activity profile of compounds.