The leather industry represents a significant environment encumbrance and it generates a great quantity of chrome shaving which is one of the solid wastes that are generated in leather processing which is common in Ethiopia unlike other countries. And currently it is being wasted in to the dumping sites or in open areas consequently creating the solid waste disposal problem for tanners. Which often determine the economic efficiency of the tannery therefore the implementation of clean technologies and waste processing is of vital importance. It’s cleaner and more economical to isolate collagen hydrolysate (CH) from chrome shavings. These wastes are important resources of producing collagen hydrolysate which can be applied in leather processing operations. The aim of this study is to prepare collagen hydrolysate from chrome shaving by bio-chemical hydrolysis process for 2hr and 3hr hydrolysis time and to apply it in wet blue sheep skin in post tanning operation to determine the optimum hydrolysis conditions and molecular weight of the collagen hydrolysate and also to determine its stabilizing effect on collagen fibers. The optimum conditions of hydrolysis for post tanning operation was determined by preparing six different types of collagen hydrolysates and apply it post tanning operation as a retanning agent. Based on the absorption of process chemicals, organoloptic properties and physical properties of the leather the best collagen hydrolysate is selected and characterized further for chromium content, fat content, and ash content and the result was found to be 1.8%, 0.45%, 1.21%. The results showed that collagen hydrolysates play a role in stabilizing collagen fibers. And also the best collagen hydrolysate for post tanning is obtained when the chrome shaving was hydrolysing for 3hr duration by 1% trypsine enzyme. And the range of the molecular weight should be in between 2000 to 6000 Daltons. It is concluded that by preparing collagen hydrolysates syntans from chrome shaving satisfactory results can be achieved by applying it in post tanning operation during leather processing and also they can be used for stabilization of collagen fibers.