The aim of the present research is determining the effectiveness and consideration of the principles of educational (instructional) designing, which is applied in cognitive load, learning and teaching in multimedia learning environments. The main concern of cognitive load has been the necessity of existence of an adjustable relationship between education and the restrictions of cognitive system of learners. Regarding the restrictions of human being’s cognitive capacity, designing various learning subjects in multimedia learning environments -based on the cognitive load- has a significant importance. This research has been selected from experimental researches pretest- posttest interfering, which has group-control (the test group has been trained according to the instructional CD based on the 14 principles of multimedia, and the control group has been trained also according to the instructional CD but without the 14 principles of multimedia). This study includes all of the counseling students of Payame Noor University of Bookan which entered the university in 1390-91; the number of the students amounts to 540 students. The specimen of the research included 180 people (110 men and 70 women) which was harmonized based on Riyun’s intelligence quotient test. Moreover, they 
were  chosen  from  two  groups:  test-group  (including  55  men  and  35 women) and control group (including 55 men and 35 women). The way of  selection  was  based  on  simple  and  casual  specimen.  Different research’s instruments include: investigated learning test, Pas’s measuring cognitive load scale, the investigated instructional software based on 14 principles of multimedia, a questionnaire with 72 questions, which has been investigated based on 14 principles of multimedia. The results of the research showed that the consideration of the principles of educational designing in relation to group evidence has a meaningful effect (P>./01), in  decreasing  cognitive  load  and  increasing  learning  of  group  test. Moreover, the relationship of each of the multiple factors (14 principles of multimedia) with cognitive load and learning was in a meaningful level.