Background : Foot core stability and active single leg stance (ASLS) combination are exercise concept to build muscle contraction synergistically which be used to increase dynamic stability. In previous study, positive result for increase dynamic stability after six weeks intrinsic foot muscle exercise. The active single leg stance (ASLS) is an exercise to facilitate recrutment postural muscle as movement background. Purpose : This study aims to to investigate combination effect of foot core stability and active single leg stance (ASLS) for dynamic balance athlete with chronic ankle instability (CAI). Material/Methodes : Experimental pre and post test design, 23 volley athletes consisting of 6 females and 17 males were randomly divide into 3 groups. One control group and two intervention group. The control group consisted of 7 peoples, group 1 and 2 consisted of 8 peoples. The intervention was given in four weeks three times a week and meassured by star excursion balance test (SEBT). Results : The foot core stability and active single leg stance (ASLS) combination showed significant dynamic stability improvement for all indicators, anterior (p= 0.000), anterolateral (p=0.001), anterolateral (p=0,00), lateral (p=0.00), posterolateral (p= 0.007), posterior (p= 0.016), posteromedial (p= 0.002), medial (p= 0.004), and anteromedial indictors (p= 0.002). Discussion : Dynamic balance improvement of all indicators in group 2 were influenced by intrinsic foot muscle contraction, form a localized stability, which spread before the occurence of joint motion. Foot core stability create synergistic connection with pelvic core, together form optimal posture and build dynamic stability.