We can control the speed of the single phase DC Motor with ease by using microcontroller and proper driving mechanism.In industries mostly coil based analog variable frequency drive is used. Because of this type of variable frequency drive there are problem rising like over current, short circuit, over voltage, under voltage, under frequency which results in unwanted tripping of the devices.We can replace this coil based analog variable frequency type with microcontroller based speed controlling mechanism. Because of this type of speed controlling, we can accurately control the speed of DC motor in operation. In addition to this, this type of controlling comparatively cheaper, reliable and accurate .It requires less maintenance and it is more convenient in use.Aim of this project is to control speed of dc motor using commands sent from mobile phone. As speed of dc motor is dependent on duration of input voltage, by changing the duration we can control the speedof the single phase dcmotor.