Operator protective structure installed on cabin of construction machine

An operator protective structure equipped on a cabin of construction machine is capable of moving the cabin along with a front guard by directly installing the front guard on the cabin fixed to an upper frame to protect the operator from an object penetrating into the front of the cabin. The cabin is provided with a bottom plate on a bottom thereof, mounted on an upper frame installed on a lower driving body and independently vibrated relative to the upper frame by connecting the bottom plate to the upper frame through vibration absorbing devices. The operator protective structure includes a front guide provided with a top bar and a bottom bar and installed up and down in front of the cabin to protect the cabin from objects penetrating into a front of the cabin and a top guide formed long on a ceiling of the cabin in a front and rear direction to protect the cabin from falling objects. The top bar is connected to a front top portion of the cabin and the bottom bar is connected to a front bottom portion of the cabin, whereby the front guide and the cabin are vibrated relative to the upper frame in a single body.