  Geometri is one of branch of the branch of mathematics that plays a major
role in the development of science and technology. Thus, knowing the geometry
concept is needed for students from their early basic level of thinking. A
preliminary study showed that the elementary students have difficulty in
perceiving parallelogram shape in a 2-dimension of a cube drawing as a square
shape. This difficulty makes the students can not solve geometrical problems
correctly. This problem is related to the internal thinking process in
geometry. We conducted the exploration of students internal thinking processes
in geometry particularly in distinguishing the square and parallelogram shape.
How the students process their internal thinking through distortion and
abstraction is the main aim of this study. Analysis of geometrical test and
deep interview are used in this study to obtain the data, The result of this
study is there are two types of distortion and abstraction respectively in
which the student used in their internal thinking processes.
