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• Wind erosion is the most environmental threat in arid and semi-arid regions. • Aridisols of south eastern Tunisia showed high values of wind erodible fraction EF. • Prediction equations of EF are not applicable for Aridisols of Tunisia. • The developed prediction equation of EF is largely different than other over world. • The developed equation showed that sand and CaCO 3 contents controlling soil EF. Wind erosion is a serious environmental threat. However, for Northern Africa estimates or predictions of the wind erodible fraction (WEF) in arid soils are rare. This study was conducted to (i) compare the flat sieve (WEF fs) and the Fryrear equation (WEF c) in order to estimate WEF (ii) fuse the directly measured WEF fs values to other measured soil parameters, i.e. soil organic matter (SOM), carbonate (CaCO 3), sand, silt and clay content, to obtain a new improved WEF equation prediction. Samples were collected at ten locations near Gabès (Southern Tunisia) at three depths (0–2.5, 2.5–5 and 5–15 cm) in cultivated or native soils. The obtained WEF fs were>80% and therefore the soils would be classified as highly wind erodible (WEF > 50%). The lowest WEF fs values were found in the cultivated soils (82.5%), ranging from 82.5 to 96.9%. Our WEF fs estimates were positively correlated to sand (r = 0.78; p < 0.001), but negatively correlated to CaCO 3 content (r = -0.82; p < 0.001). Interestingly, neither SOM nor clay content was strongly related to WEF fs. However, the WEF fs in cultivated soils was significantly linked to ∑(SOM + clay content). The Fryrear estimation predicted all WEF c values to be less than 60%. This clear mismatch to our data relates to CaCO 3 presence, high sand and low SOM content in our Tunisian soils, when compared to US soils used to establish the Fryrear method. Therefore, we established a new equation for the wind erodible fraction, WEF mod (%) = 125.83–0.59*Clay(%) − 0.22*Silt(%) − 0.25*Sand(%) + 0.29*SOM(%) −0.69*CaCO 3 (%) (r = 0.85; p < 0.001). In the studied regions of Tunisia, this equation predicts much better soil WEF. The present paper is a first study to improve WEF estimation and prediction in arid North Africa. Better predictions of WEF are crucial in combating wind erosion of soils both in North Africa and in comparable soils globally. [ABSTRACT FROM AUTHOR]