Modern speleology can profit from accurate measuring of cave climate components through long-time monitoring. Our aim is to test a set of new type of wireless temperature sensors in a cave environment. Apart from testing the new device we also want to demonstrate anthropogenic effects on the cave climate. The device is a low-cost and low consumption TELOSB wireless sensor module. The highly sensitive sensor records even the smallest changes in air temperature. These sensors are easy to manage. They allow continuous monitoring both in pits and horizontal passages of the cave and even to cover the whole extent of a cave. We measured the temperature in two caves in four time periods with 4 to 40 sensors. The number of sensors placed in a cave depends on the structure and morphology of the cave. Measurements were carried on in the warm and cold seasons and with different time spans. During the data evaluation, we checked the appropriate operation of the sensors. Our test sites were Trio Cave and Upper Szajha Cave in the Mecsek Mountains (southern Hungary). The purpose of the measurements is to survey the change in temperature caused by the visitors of the cave, depending on their number and the length of their stay in the cave. The time changes due to draft in a pit have also been investigated. From the data it can be seen that the visit of a group in the cave was accompanied by the quick rise in temperature, sometimes even more than 1 °C which returned to normal over a longer period of time.