This study identifies the influence of interdisciplinary variables on tourist online purchasing intention, such as consumers' online purchasing experience, novelty-seeking behavior, perceived ease of use, risk taking, tourism service and destination characteristics. The study population includes international tourists who purchased Yazd sightseeing tours. Using convenience sampling, 386 visitors were chosen to complete the variable scale questionnaire. The data were analyzed using SmartPLS and SPSS software. Results indicated that “prior experience,” “ease of use,” “risk taking”, and “novelty-seeking behavior” have a direct and meaningful effect on “online purchasing attitude” and have an indirect effect on “tourist online purchasing intention” with the mediating role of online purchasing attitudes. Furthermore, “tourism services and destination characteristics” and online purchasing attitudes directly and significantly affect tourists' online purchasing intentions. Moving between disciplines improves the quality of industry-relevant research and makes it more practical and valuable. The identified interdisciplinary variables influencing tourists’ online purchasing intentions are valuable for the destination marketing of World Heritage Cities.