This study aims to develop a scale regarding the identification of the existing situation for the communication effectiveness in the friendship of students, who are in the last phase of their adolescence period. This scale that developed to identify the communicative effectiveness levels of adolescent science students in their friendships has been introduced as there is no other scientific scale in the literature. The scale was finalised with statistical analyses after administration to 504 students studied in the year of 2016-17. The final version of the scale has an internal consistency coefficient of .853 and a Kaiser-Meyer-Olkin (KMO) value of 0.738. The scale consists of 37 items with a 5 point Likert scale.