Four kinds of alkaline extraction approaches, including the conventional, the oxygen-reinforced, the H₂O₂-reinforced and the oxygen-and-H₂O₂-reinforced ones （E, E0, Ep and E0p） , were used to modify ClO₂-delignified （D0） wheat straw pulp, and the modification effects of these four approaches on the subsequent bleaching stage （D1） were explored. In addition, various elemental chlorine-free （ECF） bleaching sequences, such as D0ED1, D0P, DoA/QP, D0EP, D0EpD1 and D0EpP, were comparatively investigated. The results indicate that （ 1 ） the modification effects of different alkaline extraction approaches on the residual lignin of Do stage are different from one other; （2） for the subsequent D1 stage, the bleachability of D1 pulp varies in an order of D0E0P 〉 D0Ep 〉 D0E0 〉 D0E; （3） in the D0ED1 bleaching sequences, the increase of ClO₂ dosage in D1 stage results in the brightness enhancement in a certain degree, especially at an optimized ClO₂ dosage of 0. 8% -1.0% ; （4） as compared with the other sequences, D0EpD1 and D0EpP sequences are both of better bleaching effect; and （5） with D0EpD1 and DoEpP bleaching sequences, the final brightness of bleached wheat straw pulp reaches 82.3% ISO and 83.8% ISO, respectively, which means that both D0EpD1 and DoEpP sequences are applicable to the ECF short-sequence bleaching of wheat straw pulp.