The main objective of the study is at first identifying the expectation gap about audit responsibility and the second quantifying the expectation gap in Iran. In order to collecting data, a questionnaire designed and developed between auditors and investors. Collected data analyzed by employing non-parametric statistics test. The results show that there is expectation gap between auditors and investors in Iran. The current study employed a new approach in the world in order to quantifying the expectation gap. It gives the more strength to other researchers in order to measuring audit expectation gap in the world.