Laboratory assistants experience several problems, including data collection of attendance and payroll data in laboratory assistants. This is because the recording of attendance is still using conventional methods so that it is less effective in its work and takes quite a long time to do. Payroll is a form of reward or appreciation that is given regularly to employees. In previous research, payroll applications have been designed using the Rapid Application Development (RAD) method and the PHP programming language with the MySQL database. This research aims to design a web-based payroll application for Pamulang University Informatics Engineering Laboratory Assistants using the RAD method. Data collection methods used in this research are literature study and observation. Furthermore, the current system analysis and the proposed system analysis were carried out. In addition, the user interface of the payroll system is also designed. Based on system functionality testing using whitebox testing and blackbox testing methods, it produces a payroll application design for web-based Informatics Engineering laboratory assistants at Pamulang University using the RAD method and this application design has succeeded in fulfilling one of its objectives, namely making it easier for laboratory assistant administrators to record the attendance of laboratory assistants, because with this system the recording of laboratory assistant attendance which previously took 2 days to 3 days became only 5 minutes, and data recording which still uses conventional methods so that it is prone to miscalculations and loss of data on laboratory assistant attendance and laboratory assistant payroll data. The conclusion of this research is that the design of this payroll application has been able to meet the needs of laboratory assistants and can fulfill all the objectives of the application design.