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Surface-applied biosolids can affect the physical properties of the topsoil and promote the rehabilitation of degraded soils. In this study,, the effects of time after biosolids application (1-3, 6, 12, and 18 months) and biosolids application rate (0, 7, 18, 34, and 90 Mg ha(-1)) were assessed on selected physical soil properties, from shrubland (Ustic Calciargid) and grassland (Vertic Paleargid) soils. The bulk density (BD) of the 0- to 2.5-cm soil depth was significantly (P less than or equal to 0.05) affected in the two soils and decreased approximately 10% in the 90 Mg ha(-1) I treatment with respect to the 0 Mg ha(-1) treatment. Time-to-runoff (TR) in the grassland soil and infiltration rate (IR) in the shrubland soil were significantly affected (P less than or equal to 0.05) by time after biosolids application, and both TR anti IR were significantly increased (P less than or equal to 0.05) by rate of biosolids application in the two soils. For the shrubland soil treated 18 months before rainfall application, TR and IR increased from 74 see and 23.7 mm hr(-1) in the 0 Mg ha(-1) treatment to 446 see and 104.2 mm hr(-1) in the 90 Mg ha(-1) treatment. Organic matter (OM) content in the 0- to 3-cm soil depth of the two soils significantly, increased as rate of biosolids application increased. Clay, dispersibility significantly, (P less than or equal to 0.05) decreased in the 0- to 3-cm soil depth of the soils treated with 90 Mg ha(-1) of biosolids as compared to untreated soils. However, neither rate, nor time after biosolids application affected the OM contents, the BD, or CD of the 3- to 8-cm soil depth in any of the two soils. Surface-applied biosolids have the potential to increase the TR and IR of degraded soils, but 18 months after application at rates as high as 90 Mg ha(-1), biosolids only affected the physical characteristics of the 0- to 3-cm soil depth.