The present invention relates to a device and methods for filtering anti-collision alerts for aircraft having a locating system charting the position of the aircraft and estimating the precision of its position. A navigation system of the aircraft calculates at least the actual speed of the aircraft, the speed instruction and a first deviation between the instruction and the actual speed, and the deviation being compared with a first reference overshoot threshold. An anti-collision system generates alerts. An alarms manager of the aircraft centralizes the alerts transmitted by the terrain anti-collision equipment of the aircraft to the crew. The alerts each posses a coding of the danger level, and the danger levels form part of a first predetermined set. The alert filter according to the invention filters sets of alerts according to the coding of their danger level.