The data supports the manuscript entitled “In-cloud discharge of positive cloud-to-ground lightning and its influence on the initiation of tower-initiated upward lightning,” and MATLAB can open these *.mat files. The *.mat contains waveforms of fast electric field change, slow electric field change, VHF waveform, and located radiations. The data *.cine can be opened by Phantom Camera Control software that can be download from this link: https://www.phantomhighspeed.com/resourcesandsupport/phantomresources/pccsoftware The data can be used freely for scientific purposes with the appropriate citation.