A heating circuit of an atomization device, comprising a heating resistor and an MCU, wherein the heating circuit further comprises a sampling resistor, a first driving unit and a second driving unit, and the resistance value (R 1) of the sampling resistor is greater than the resistance value (R 2) of the heating resistor, wherein the MCU is configured to control the first driving unit through a corresponding IO port to enable a battery power supply to only supply power to the heating resistor in a first time period of a PWM period so as to enable the heating resistor to work; the MCU is configured to control the second driving unit through a corresponding IO port to enable the battery power supply to supply power to the sampling resistor and the heating resistor which are connected in series in a second time period of the PWM period, and respectively to collect the voltage of the heating resistor and the voltage of the sampling resistor through one or more corresponding IO ports, and to calculate the resistance value (R 2) of the heating resistor according to the resistance value (R 1) of the sampling resistor and the collected voltages; wherein the heating circuit is characterized in that the first driving unit comprises a PMOS transistor, a switching device (Q3, Q4), a third resistor and a fourth resistor, wherein a first IO port of the MCU is respectively connected with a control end of the switching device (Q3, Q4) and a first end of the fourth resistor; a first end of the switching device (Q3, Q4) and a second end of the fourth resistor are respectively electrical grounding, a second end of the switching device (Q3, Q4) is respectively connected with a gate of the PMOS transistor and a first end of a third resistor, a source electrode of the PMOS transistor and a second end of the third resistor are respectively connected with a battery power supply, and a drain electrode of the PMOS transistor is connected with a first end of the heating resistor; a second end of the heating resistor is electrical grounding. the MCU is configured to control the first driving unit through a corresponding IO port to enable a battery power supply to only supply power to the heating resistor in a first time period of a PWM period so as to enable the heating resistor to work; the MCU is configured to control the second driving unit through a corresponding IO port to enable the battery power supply to supply power to the sampling resistor and the heating resistor which are connected in series in a second time period of the PWM period, and respectively to collect the voltage of the heating resistor and the voltage of the sampling resistor through one or more corresponding IO ports, and to calculate the resistance value (R 2) of the heating resistor according to the resistance value (R 1) of the sampling resistor and the collected voltages; wherein the heating circuit is characterized in that the first driving unit comprises a PMOS transistor, a switching device (Q3, Q4), a third resistor and a fourth resistor, wherein a first IO port of the MCU is respectively connected with a control end of the switching device (Q3, Q4) and a first end of the fourth resistor; a first end of the switching device (Q3, Q4) and a second end of the fourth resistor are respectively electrical grounding, a second end of the switching device (Q3, Q4) is respectively connected with a gate of the PMOS transistor and a first end of a third resistor, a source electrode of the PMOS transistor and a second end of the third resistor are respectively connected with a battery power supply, and a drain electrode of the PMOS transistor is connected with a first end of the heating resistor; a second end of the heating resistor is electrical grounding.