The structure of trans butadiene-isoprene copolymer rubber(TBIR) involved in chlorination reaction is complex, and its derivative, chlorinated trans-1,4-poly(butadiene-co-isoprene) rubber(CTBIR), achieves rubber elasticity and polarity mainly depending on its double bond and allyl chloride structures. This article aims to regulate the double bond and allyl chloride structure in CTBIR by controlling the chlorination reaction conditions, such as chlorination time, temperature, chlorine gas introduction methods, free radical scavengers, and UV irradiation. A high initial reaction temperature preserves the double bond content in CTBIR while reducing its chlorine content. The method of circulating chlorine gas facilitates achieving high chlorine content while maintaining high double bond content. The adding of 2,2,6,6-tetramethylpiperidyl-1-oxyl(TEMPO) is beneficial for maintaining the double bond content in CTBIR. The allyl chloride structure in CTBIR can be regulated by reaction temperature, reaction time and the addition of TEMPO. Regulating the structure of chlorination product provides a basis for the halogenation reaction of rubber. The regulation of halogenation products can provide the selection of reaction sites for the subsequent structural modification of CTBIR.