The purpose of the this study was to determine the comparative analysis of body muscle activities in plank exercise with and without thera-band. Twelve healthy adult males(age, $21.75{\pm}.57$ years; height, $173.33{\pm}1.34cm$; body mass, $65.92{\pm}1.64kg$; and BMI, $21.93{\pm}.46kg/m^2$) participated in this study as subjects. Plank exercises(full, elbow, side, and reverse plank) were performed with four different thera-band in without(WT), red color(RT), blue color(BT), and siver color(ST). We measured the muscle activities of the erector spinae(ES), deltoideus p. acromialis(DA), external oblique(EO), rectus abdominis(RA), rectus femoris(RF), latissimus dorsi(LD), pectoralis major(PM), and biceps femoris(BF). The research findings were as follows. ES and DA muscle activities were greatest during full plank performed with the WT(p<.05). EO, RA, RF, and PM muscle activities were greatest during full plank performed with the ST(p<.05). ES and DA muscle activities were greatest during elbow plank performed with the WT(p<.05). RF and PM muscle activities were greatest during elbow plank performed with the ST(p<.05). ES, EO, RA, RF, LD, PM, and BF muscle activities were greatest during side plank performed with the ST(p<.05). DA, EO, RA, RF, LD, PM, and BF muscle activities were greatest during reverse plank performed with the ST(p<.05). These results are expected to serve as reference materials for plank exercise applications in training programs for body muscle strengthening.