Information on marine litter in general and beach litter in particular from Sudan and to some extent from the Red Sea region is insufficient. The aim of this study is to assess the beach litter composition, distribution, and abundance in some selected beaches of the World Heritage Site of Dungonab Bay and Mukkawar Island National Park (DMNP) located in Sudan, Red Sea coast, and to examine the rate of beach litter flux and the cleanliness of its beaches in order to provide baseline information for beach litter management at DMNP. A total of 6 sites were investigated for beach litter over a 10-month period from January to October 2017 on a quarterly basis. A total of 24 collections of beach litter were performed covering a stretch of 600 m or 7700 m2 of DMNP coastline. In total, 3037 beach litter items were collected during the study time from DMNP with an overall average of 506.2 ± 409.8 items/100 m (0.4 items/m2). Plastic beach litter was the most abundant (1738 items), constituting 57.23% with an average density of 289.7 ± 242.2 items/100 m (0.23 items/m2). The beaches of DMNP were clean (CCI = 4.6) at the time of the study. The rate of flux of the beach litter decreased steadily from 21.9 to 16.43 items/100 m/day with an overall average of 18.82 ± 2.8 items/100 m/day. The gradual decrease in the net accumulation of beach litter over the period of the study suggests that the beach litter at DMNP was likely of a local land-based origin and the beaches of DMNP are not a potential sink of marine litter. The determination of the rate of flux of beach litter is a reasonable indicator of the dynamics of beach litter in DMNP. Accordingly, application of preventive measures accompanied with awareness activities and investment in plastic collection and recycling would further enhance and preserve the present status of beach cleanliness and encourage tourism activities.