Based on the observation data of daily maximum/minimum temperature and daily relative humidity from 116 national meteorological stations in Shandong between June and August from 1961 to 2022, the spatiotemporal distributions and variations of three types of heat waves, including daytime type, nighttime type and compound type, are analyzed using the total number, average duration, average intensity and average relative humidity indices. The results are as follows. (1) The spatial distributions of the three types are significantly different, because the daytime type is more in the west and less in the east of Shandong, the nighttime type is more in the south and less in the north of Shandong, and the compound type is more in the south of Shandong and less in Shandong Peninsula. The average duration of the three types is less than 4.5 d in most areas of Shandong. The average intensity of the compound type is higher than 8.0 ℃ in the west and middle of Shandong. The average relative humidity of the nighttime type is obviously larger than that of the daytime and nighttime types, with the average relative humidity commonly over 76%. (2) The three types of heat waves mainly occur in July. In June, it is mainly the daytime type and its duration is the longest, accompanied with the lowest relative humidity. Both in July and August, the average duration of the compound type is the longest. The average relative humidity is the highest in August for all the three types, and the average relative humidity of the nighttime type is the highest among three months. (3) The average relative humidity of the daytime type in Shandong shows a significantly decreasing trend, while the total number, average duration and average intensity of the nighttime and compound types display a significantly increasing trend. (4) The number of stations with the daytime type presents an insignificantly decreasing trend, but the number of stations with the nighttime and compound types reveals a significantly increasing trend. Around the mid-1990s, the nighttime and compound types obviously increased.