The purpose of this paper is to contribute to the growing body of research on viral advertising messages which is based on viral marketing, while concentrating on trust of viral advertising messages and its effect on attitude and consumer behavior intention. To achieve the objectives of this study, we used marketing technology and techniques specific to viral marketing. The implementation of the study depended on a questionnaire (with 27 items) used to collect the required data from 305 customers. The information collected was based on a primary exploration study with the purpose of constructing and designing a study model. Six hypotheses were proposed based on literature related to viral marketing, viral advertising messages and behavior intention. The study model was divided into six dimensions. The first four was concerned with trust of viral advertising messages, the fifth with attitude and customer behavior intention, while the sixth focused on the correlation between components of the study model.Many descriptive statistical methods were used, e.g., one sample T-test, Pearson's Correlation for the statistical analysis. The indicated results accepted all six hypotheses (assumed for each dimension). Consequently, there was an impetus to achieve trust of viral advertising messages on all attitudes and customer behavior intention.Although this study was limited, it tried to use many factors to test trust effect of viral advertising messages on attitudes and consumer behavior intention. It is considered as an attempt that can be developed for future studies.