Indonesia is an agricultural country. Where has a very wide agricultural land. According to BPS data for 2022, Indonesia has an agricultural area of 10.6 million ha. With such a large land area, of course, Indonesia has a diversity of crops in the agricultural sector. A lot of yields make farmers and farmer groups sometimes have problems in marketing their products. So that many farmers do not benefit from the harvest. The use of information technology is expected to be able to overcome the problems faced by farmers in marketing their crops. One of them is by using the marketplace. By using this marketplace application it is expected to increase profits from the harvest. The existence of this marketplace platform can be used as an alternative for agricultural entrepreneurs and collectors or middlemen as their business media, then this marketplace platform can introduce business activities online. Black box testing is testing carried out to observe the results of applications that are ready to be made to test input and output functionality, so that they can function properly without knowing the code structure and testing can be applied to unit, integration, system and acceptance testing. Based on the test results using the black box testing method, there are 7 test models namely the register page, login, main, edit profile, store registration, add products and checkout with a total of 50 users, the results obtained are 93% of successful users and unsuccessful users. The results of unsuccessful use of black box testing occur due to network interference or inappropriate input from the user. Then it can be concluded that this marketplace application is suitable for use as a means of transaction.