Malaysia is a country that's also facing the challenges with the consequences of a cashless society related to particularly developing cashless transaction behaviour in higher education institutions. It’s also required to solve the challenges of the Covid-19 pandemic, to reduce cash transactions behaviour. This study aims to determine the validity and reliability of key elements of cashless transactions behaviour instrument. Attitudes, subjective norms, perceived behaviour control, intention, behaviour in cashless transactions, perceived trust, perceived usefulness, perceived cybersecurity, transaction procedures, perceived hidden costs, motivation to comply, social norms, and self-efficacy are the main elements of cashless transactions behavior in this study. A total of 30 Kolej Komuniti Pasir Gudang residents who were users of cashless transactions were involved as samples in this study. Therefore, to ensure that this questionnaire is verified and reliable researchers do the validity as well as the pilot study. The first phase of the validity phase was implemented by giving a questionnaire to two face validity experts and two content validity experts. The quantitative measurement method through the Content Validity Index (CVI) has been used to evaluate the items whether they should be retained or dropped. According to the results, the Item Content Validity Index (ICVI) for this study achieved 1.00. After obtaining expert reviews and validity as well as CVI analysis, all the reviews were improved to continue the reliability phase through the pilot study. Next, the instrument reliability phase is implemented. The results obtained were analyzed using the Rasch Measurement Model with a WinSteps version 3.69 to examine the item and person reliability. Additionally, the item measure quality was assessed by analyzing the PTMEA CORR, infit and outfit MNSQ values to examine the construct validity. The results also showed the reliability of instrument items was 0.81 and the person reliability index was 0.98 which show that this instrument is reliable and acceptable with a high level of consistency for measuring the instrument for cashless transactions behavior element. While all the PTMEA CORR is in positive values which show that the item can differentiate the ability of the respondent.