The invention provides an RSSI detection based tracking and positioning method and system. The RSSI detection based tracking and positioning method comprises the steps of setting at least a reader to enable a signal range to cover all the possible paths; receiving a positioning data packet sent by a handheld device in a first period through a directional antenna by a radio frequency transceiver module, and determining a corresponding time stamp t and a corresponding RSSI value and sending the time stamp t and the RSSI value to a server by a processor; storing the data points in a positioning information database; by the server, opening a time window in a second period, and performing function fitting for at least two corresponding data points of each directional antenna by using a detection function f (t, rssi); correspondingly generating a curvature-time curve for each directional antenna; and by the server, obtaining multiple groups of curvature-time relation curve sections greater than an effective threshold value based on the curvature-time curves, generating a curvature-time relation curve, and obtaining the position-time positioning curve of the handheld device based on the position of one directional antenna corresponding to each peak value in the curvature-time relation curves of the multiple antennas.