Genetic analysis and fine mapping of genes controlling leaf rolling were conducted using two back-crossed generations (BC4F2, BC4F3) derived from a cross between QMX, a non-rolled leaf cultivar as a recurrent par-ent, and JZB, a rolled leaf NIL of ZB as a donor parent. Re-sults indicated that leaf rolling was mainly controlled by an incompletely recessive major gene, namely rl(t), and at the same time, affected by quantitative trait loci (QTLs) and/or the environment. A genetic linkage map was constructed using MAPMAKER/EXP3.0 with eight polymorphic mark-ers on chromosome 2, which were screened by BAS method from 500 SSR markers and 15 newly developed inser-tion/deletion (InDel) markers. The position of rl(t) was esti-mated with composite interval mapping (CIM) method using WinQTLcart2.5. Gene rl(t) was mapped between markers InDel 112 and RM3763, and 1.0 cM away from InDel 112 using 241 plants in BC4F2 population. To fine map rl(t), one BC4F3 line with 855 plants was generated from one semi-rolled leaf plant in BC4F2. Four new polymorphic InDel markers were developed, including InDel 112.6 and InDel 113 located between markers InDel112 and RM3763. Based on the information of recombination offered by 191 rolled leaf plants and 185 non-rolled leaf plants from the BC4F3 line ,we mapped rl(t) to a 137-kb region between markers InDel 112.6 and InDel 113. Homologous gene analysis sug-gested that rl(t) was probably related to the process of leaf development regulated by microRNA. Genetic analysis and fine mapping of genes controlling leaf rolling carried conducted using two back-crossed generations (BC4F2, BC4F3) derived from a cross between QMX, a non-rolled leaf cultivar as a recurrent par- ent, and JZB, a rolled leaf NIL of-ZB as a donor parent. Re-sults indicated that leaf rolling was mainly controlled by an incompletely recessive major gene, ie rl (t), and at the same time, affected by quantitative trait loci (QTLs) and / or the environment. A genetic linkage map was constructed using MAPMAKER / EXP 3.0 with eight polymorphic mark-ers on chromosome 2, which were screened by BAS method from 500 SSR markers and 15 newly developed in-use / deletion (InDel) markers. The position of rl Gene rl (t) was mapped between markers InDel 112 and RM3763, and 1.0 cM away from InDel 112 using 241 plants in BC4F2 population. To fine (t) was esti- mated with composite interval mapping (CIM) method using WinQTLcart 2.5. map rl (t), one BC4F3 line with 855 plants was generated from on Four new polymorphic InDel markers were developed, including InDel 112.6 and InDel 113 located between markers InDel112 and RM3763. Based on the information of recombination offered by 191 rolled leaf plants and 185 non-rolled leaf plants from the BC4F3 line, we mapped rl (t) to a 137-kb region between markers InDel 112.6 and InDel 113. Homologous gene analysis sug-gested that rl (t) was probably related to the process of leaf development regulated by microRNA.