A system for presence detection in an environment to be monitored, comprising: - a processing unit; - an electrostatic charge sensor, coupled to the processing unit, configured to detect an electrostatic charge in said environment and generate an electrostatic charge signal (Vd'), wherein, in a starting condition of absence of presence in the environment to be monitored, the processing unit is configured to: a. acquire a first electrostatic charge signal (Vd'), b. sample said first electrostatic charge signal (Vd'), and generate a first sampled signal (S Q) formed by a plurality of first samples (xl-xN), c. for each first sample (x1-xN), calculate the derivative with respect to time, and generate a first derivative signal formed by a respective plurality of second samples (yl-yN), each first sample and respective second sample being coordinates of a respective one of a plurality of first points (P1-PN) in a biaxial reference system, d. calculate a first mean value (xC) of a plurality of, or all, said first samples (xl-xN), e. calculate a second mean value (yC) of a plurality of, or all, said second samples (yl-yN), and f. define a circular base shape, calculating a radius of a circumference having a geometric center having as coordinates (xC, yC) the first (xC) and the second (yC) mean values and enclosing all said first points (P1-PN) in the biaxial reference system; wherein, in an operating condition successive to said starting condition, the processing unit is configured to: g. acquire a second current electrostatic charge signal (Vd'), h. sample said second electrostatic charge signal (Vd'), and generate a second sampled signal (S Q) formed by a plurality of third samples (xl-xN), i. for each third sample (x1-xN), calculate the derivative with respect to time, and generate a first derivative signal formed by a respective plurality of fourth samples (yl-yN), each third sample and respective fourth sample being coordinates of a respective second point (P1'-PN') in the biaxial reference system, j. verify whether one or more of the second points (P1'-PN') have coordinates, in said biaxial reference system, outside said circular base shape, and k. generate a detection signal of said presence in the monitored environment in response to verifying that one or more of the second points have coordinates, in the biaxial reference system, outside the circular base shape. - a processing unit; - an electrostatic charge sensor, coupled to the processing unit, configured to detect an electrostatic charge in said environment and generate an electrostatic charge signal (Vd'), a. acquire a first electrostatic charge signal (Vd'), b. sample said first electrostatic charge signal (Vd'), and generate a first sampled signal (S Q) formed by a plurality of first samples (xl-xN), c. for each first sample (x1-xN), calculate the derivative with respect to time, and generate a first derivative signal formed by a respective plurality of second samples (yl-yN), each first sample and respective second sample being coordinates of a respective one of a plurality of first points (P1-PN) in a biaxial reference system, d. calculate a first mean value (xC) of a plurality of, or all, said first samples (xl-xN), e. calculate a second mean value (yC) of a plurality of, or all, said second samples (yl-yN), and f. define a circular base shape, calculating a radius of a circumference having a geometric center having as coordinates (xC, yC) the first (xC) and the second (yC) mean values and enclosing all said first points (P1-PN) in the biaxial reference system; g. acquire a second current electrostatic charge signal (Vd'), h. sample said second electrostatic charge signal (Vd'), and generate a second sampled signal (S Q) formed by a plurality of third samples (xl-xN), i. for each third sample (x1-xN), calculate the derivative with respect to time, and generate a first derivative signal formed by a respective plurality of fourth samples (yl-yN), each third sample and respective fourth sample being coordinates of a respective second point (P1'-PN') in the biaxial reference system, j. verify whether one or more of the second points (P1'-PN') have coordinates, in said biaxial reference system, outside said circular base shape, and k. generate a detection signal of said presence in the monitored environment in response to verifying that one or more of the second points have coordinates, in the biaxial reference system, outside the circular base shape.