A warp tension controlling apparatus in a weaving machine for weaving a pile fabric, the waving machine includes a pile warp beam (22) and ground warp beam (1) in which the weaving machine performs negative easing of one or more ground warps (T) by swinging a biased tension roller (3), characterized in that the apparatus includes: a first biasing portion for providing a first biasing force to the tension roller (3) during a pile weaving step; and a second biasing portion for providing a second biasing force to the tension roller (3) during a border weaving step performed between the pile weaving steps, in addition to the first biasing force by the first biasing portion.