The aim of the study is to teach the concept of function using cryptology and to investigate whether it provides support to students who have difficulty integrating this topic into everyday life. The study's research group consisted of 50 elementary school teachers in the department of mathematics education at a public college in Ankara. Since the study aimed to show the advantages and disadvantages of using cryptology in teaching the basic function concept, qualitative data were collected and analyzed. The data collection instrument of the study is a performance test which consists of 10 questions prepared by an observer, a practicing researcher and an evaluation expert. This performance test was used as both pretest and posttest. For the functions, only function definition, inverse function, one-to-one function, set of values, set of definition, set of images, and cryptography were used where functions can be used in daily life. As a result of the study, it was found that the prospective teachers' awareness of functions has increased and it is beneficial and possible to use cryptology to relate functions to daily life.