We have synthesized a new series of chromium-group 15 dihydride and hydride complexes [H2As{Cr(CO)(5))(2)](-) (1) and [HE{Cr(CO)(5)}(3)](2-) (E = As, 2a; E = Sb, 2b), which represent the first examples of group 6 complexes containing E-H fragments. The contrasting chemical reactivity of 2a and 2b with organic halogen derivatives is demonstrated. The reaction of 2a with RBr (R = PhCH2, HC drop CCH2) produces the RX addition products [(R)(Br)As{Cr(CO)(5)}(2)](-) (R = PhCH2, 3: R = C3H3, 4), while the treatment of 2b with RX (RX = PhCH2Br or HC drop CCH2Br, CH3(CH2)(5)C(O)Cl) forms the halo-substituted complexes [XSb(Cr(CO)(5)}(3)](2-) (X = Br, 5; X = Cl, 6). Moreover, the dihaloantimony complexes [XX'Sb{Cr(CO)(5)}(2)](-) can be obtained from the reaction of 2b with the appropriate organic halides. In this study, a series of organoarsenic and antimony chromium carbonyl complexes have been synthesized and structurally characterized and the role of the main group on the formation of the resultant complexes is also discussed.