GSM based smart home system a system developed to remotely control and monitor multiple home appliances and detect intrusion using a cellular phone. This system is based on GSM network technology for the transmission of SMS from sender to receiver. SMS sending and receiving is used for ubiquitous access of appliances and allowing breach control at home. The system proposes two sub-systems. The appliance control subsystem enables the user to control home appliances remotely whereas the security alert subsystem provides remote security monitoring. The system is capable enough to instruct users via SMS from a specific cell number to change the condition of the home appliance according to the user's needs and requirements. The system is capable enough to instruct users via SMS from a specific cell number to change the condition of the home appliance according to the user's needs and requirements. The second aspect is that of security alert which is achieved in a way that on the detection of intrusion the system allows automatic generation of SMS thus alerting the user against security risk