Accurate identification of heat waves holds significant importance for understanding and addressing extreme weather phenomena. Utilizing data from 33 meteorological stations in Chongqing municipality spanning 1961-2022, a daily maximum temperature threshold is employed to identify heat waves, comprehensive analyses of spatiotemporal changes in heat waves are conducted through the integration of key metrics such as the heat wave magnitude index and maximum temperature, while the evolutionary process of representative heat waves is also dissected. Key findings include: 1) The annual average heat wave magnitude index in Chongqing Muncipality ranges from 2.2 to 7.5, with the annual average maximum temperatures oscillating between 36.3 to 41.3 ℃. Both metrics show higher values in the west and northeast, contrasting with lower values in the east. The annual average start time for these heat waves lies between July 12th and August 12th, with the annual average end time ranging from August 2nd to August 19th. The annual average duration of these heat waves was found to be 4.9~7 days. The central and western regions typically experienced these events later than the southeastern areas. 2) From 1961 to 2022, there has been an overall increase in the number of heat waves, the average heat wave magnitude index, and the average maximum temperature in Chongqing Muncipality. This upward trend has became pronounced since the 1990s. The onset and end times of these heat waves have also shifted later. Furthermore, the duration of a single heatwave has increased from 4~5 days to 6~8 days. 3) In 2022, the average heat wave magnitude index of typical heatwaves occurring in Chongqing Muncipality was 36.1, with an average maximum temperature reaching a staggering 42.5 ℃. Heat waves lasted on average for 21 days, typically concentrated in mid-August. The results reveal the spatiotemporal variation patterns of heatwaves in Chongqing Muncipality, providing references for future heatwave disaster prevention and control.