The solar tracker having a bidirectional limit switch device comprises at least one solar panel (10) supported on a pivoting structure (12) tiltable in opposite first and second directions about a rotation axis (13) by a DC electric motor (M) a controller (14) and an actuator (15) controlling actuation of the electric motor (M), an inclinometer (16) fixed to the pivoting structure (12) and connected to the controller (14) to detect an actual physical positive or negative tilt angle of the solar panel (10) with respect to a horizontal plane, and a feed circuit (17) to apply a voltage having a selected polarity to the actuator (15) to produce rotation of the electric motor (M) either in the first direction or in the second direction. The actuator (15) comprises MOSFET-type first and second actuator transistors (Q1, Q2), each having a drain terminal (D), a source terminal (S) and a gate terminal (G), the first and second actuator transistors (Q1, Q2) having the drain terminals (D) respectively connected to first and second terminals (A, B) of the electric motor (M), the source terminals (S) respectively connected to first and second output terminals (1, 2) of the feed circuit (17), and the gate terminals (G) connected via the controller (14) to the inclinometer (16), and first and second diodes (D1, D2) connected in parallel between the drain terminals (D) and the source terminals (S) of the first and second actuator transistors (Q1, Q2) providing a bypass current path from the source terminals (S) of the first and second actuator transistors (Q1, Q2) to the first and second terminals (A, B) of the electric motor (M), and wherein either the first or the second actuator transistor (Q1, Q2) is put in an off state causing stop of the electric motor (M) upon receiving a positive or negative limit signal delivered by the inclinometer (16) when tilting of the pivoting structure (12) reaches a positive or negative limit tilt angle (PLTA, NLTA), the bypass current path provided by the corresponding first or second diode (D1, D2) allowing the electric motor (M) to turn in an opposite direction when an inverted voltage is applied.