Abstract Watermelon Chlorotic Stunt Virus (WmCSV) is a bipartite geminivirus residing in the genus Begomovirus (family Geminiviridae) and is whitefly transmitted (Bemisia tabaci). WmCSV infects members of the Cucurbitaceae, and represents a considerable threat to melon and watermelon crops in Sudan, Yemen, and Iran. One hundred twenty‐eight melon accessions, mostly collected from Sudan, were screened in the open‐field in Sudan under severe whitefly inoculation pressure in order to identify sources of resistance to WmCSV. One WmCSV resistant line HSD 2445‐005 selected from this first screening along with 22 new melon accessions were agro‐inoculated with an infectious Sudanese clone of WmCSV. Ten accessions exhibited resistance to WmCSV infection upon agro‐inoculation. Six of them were confirmed to have complete resistance to WmCSV through graft‐inoculation as well as multiple field trials in Sudan. These lines include the Sudanese accession HSD 2445‐005, the South African accession PI 282448, and three Indian accessions: 90625, PI 124112, and PI 414723. Resistant plants exhibited no disease symptoms, and virus DNA could not be detected by hybridization with a WmCSV‐specific probe.