Abstract: The paper ARM Based Agricultural Field Monitoring System using GSM is mainly focused on modernizing the irrigation technology in agriculture and also to provide adequate irrigation in particular area. The set up consists of mainly ARM7TDMI core and GSM. GSM serves as an important part as it is responsible for controlling the irrigation on field and sends them to the receiver through coded signals. GSM operates through SMS and is a link between ARM processor and centralized unit. ARM7TDMI is an advanced microprocessor and forms the heart of the system. Our project aims at modernizing the agricultural technology by programming the components and building the necessary hardware to automate farming. This project is mainly used to detect the exact field condition as well as weather conditions in real time .The information is given on user request in the form of SMS. GSM modem is controlled with the help of standard set of AT (Attention) commands. These commands are used to control majority of the functions of GSM modem.