The effects of polyethylene（PE） fiber and its combinayion with fine rubber particles on the flexural damage mode， peak strength， energy absorption characteristics， and flexural toughness of foam concrete were investigated， and the mechanism of action was explored by combining pore structure analysis with microscopic morphological observation. The results show that PE fibers cause the multiple cracking modes of the foam concrete and significantly improve the peak strength， energy absorption capacity， and flexural toughness of the foam concrete specimens. Combining with fine rubber particles can further enhance the specific energy absorption and flexural toughness of the foam concrete specimens. The incorporation of PE fibers could reduce the average pore size of the foam concrete. Combining with fine rubber particles leads to an increase in the average pore size and the number of coupled pores， which has a negative impact on the peak strength of the foam concrete specimens. The main reasons for PE fiber and combination with fine rubber particles to enhance the flexural toughness of foam concrete are their weakening of stress concentration at the crack tip and enhancement of energy dissipation.