The invention relates to regenerated rubber modified by utilizing trans-butadiene-isoprene rubber as well as a preparation method and application thereof. The trans-butadiene-isoprene rubber modifiedregenerated rubber is prepared from the following components in parts by weight: 95 to 50 parts of regenerated rubber, 5 to 50 parts of the trans-butadiene-isoprene rubber TBIR, 2.5 to 50 parts of filling, 1.5 to 4 parts of zinc oxide, 0.1 to 0.6 part of stearic acid, 0 to 5 parts of homogenizing agent, 0.8 to 5 parts of sulfur, 0.5 to 3.5 parts of accelerant, 0.1 to 3 parts of anti-aging agent and 0 to 2.0 parts of anti-reversion agent. According to the preparation method, the regenerated rubber is modified by adopting the trans-butadiene-isoprene rubber TBIR; the dispersity of the filling can be improved; vulcanized rubber is increased by 30 to 70 percent in tensile strength, by 40 to 100 percent in 300-percent stress at definite elongation, by 10 to 20 percent in abrasion performance and by 100 to 700 percent in flexural fatigue performance. The regenerated rubber can be used for a tire tread, a tire side, a tire body, a belted layer and an airtight layer of a tire, a highway pavement and a runway and the dynamic fatigue performance is improved.