The aim of this study is to develop the scale to assess cognitive distortions of high school students related to academic achievement and test its psychometric properties. The study group of the research, 340 for the exploratory factor analysis ( = 16,28; Sd= 1,07); 218 for the confirmatory factor analysis ( = 15,8; Sd= 1,40) and 48 for the test retest reliability, is made up of 606 people (334 female, 269 male). During the development process of the scale; from student interviews, literature and expert opinions, a 52- item form was obtained. Firstly, exploratory factor analysis (EFA) was performed on the 52 items form. As part of the EFA and expert opinions, 27 items were removed from the tool and a four-factor, 25-item form was obtained explaining 50.87% of the total variance. The next, confirmatory factor analysis (CFA) was carried out and the findings (X2/sd= 2.29; RMSEA= .08; CFI= .95; NNFI= .95; SRMR= .08) showed that the four factor model has sufficient fit-indexes. The dimension of the tool that includes the statement of catastrophy of failure is called “Catastrophizing.” while the dimension define the personal value through academic achievement is called “Self- value”. The third dimension of the scale is called “Outer attribution” since it is including statements that attributes the achievement or failure to the outer factors and lastly the dimension contains the rigid and high standards of achievement is called “Perfectionism”. Cronbach’s alfa internal consistency coefficient (.89), test retest reliability (.89) and structural reliability (.94) analyses proved that the scale had adequate reliability values. The findings obtained from all the analyses above revealed that this scale of 25 items is a valid and reliable measurement tool to evaluate the cognitive distortions of high school students related to academic achievement.