Purpose : The purpose of this study was to survey on binocular fusion step and functional degree in synoptophore. Methods : we evaluated the binocular simultaneous, fusion and stereopsis conditions of pre and post phoria of 67 adult patients (male 50, female 17) from synoptophore and Vongrafe phoria method. Results : Average of phoria were -1.25±0.43b., phoria distributions were 1 to 7 prism. exophoria much more than esophoria. Esophoria distributions were 1 to 4 prism. Correlation of steropsis according to phoria degree, it was increased in process exophoria to esophoria (r = 0.409. p < 0.001). It were simultaneous perception post corrected phoria better than pre corrected phoria (t = 6.178, p = 1.479E-8). Fusion step were compared pre of corrected phoria to post of corrected phoria, simultaneous perception of pre corrected phoria were 2.05± 1.48°. fusion were 4.31±1.92°, stereopsis were 8.33±3.33°, simultaneous perception of post corrected phoria were 1.37±0.44°, fusion were 3.31±0.92°. stereopsis were 6.54±2.12°. It were fusion post of corrected phoria better than pre of corrected phoria (t = 6.178, p = 1.479E-8). Conclusions : ln these results. phoria degrees were small in synoptophore rather than in Vongrafe method. synoptophore method were evaluated functional fusion degree of vinocular vision, post of corrected phoria were improved simultaneous perception, fusion. stereopsis before pre of corrected phoria.