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Abstract. Alkali hydrolysable nitrogen is one of the important indexes to evaluate the recent nitrogen supply capacity of coco-peat. Nutrient levels of crops is directly influenced by the level of coco-peat alkali hydrolysable nitrogen content. Alkaline reaction time, alkaline reaction temperature, NaOH solution concentration and NaOH solution addition volume are the main factors of affecting determination of alkali hydrolysable nitrogen based on the principle of alkali N-proliferation method. Effects of above four factors on determination of alkali hydrolysable nitrogen in coco-peat were studied by a series of experiments. Results of alkali hydrolysable nitrogen determination in coco-peat experiments indicated that alkaline reaction time, alkaline reaction temperature and NaOH solution concentration had significant influence on determination of alkali hydrolysable nitrogen, but NaOH solution addition volume had no significant impact on determination of alkali hydrolysable nitrogen. Relationship between determination results of alkali hydrolysable nitrogen and alkaline reaction time was fitted well by power function, and the relationship between determination results of alkali hydrolysable nitrogen and the product variable of temperature and time of alkaline reaction and NaOH solution concentration were also fitted well by logarithmic function. Ultimately, the optimum experimental conditions for determination of alkali hydrolysable nitrogen in coco-peat by alkali N-proliferation method were obtain as follows: the product of temperature and time of alkaline reaction is 900, concentration of NaOH solution is 2.2mol/L and added volume of NaOH solution is 10ml. The above results can provide a reference for determination of the content of alkali hydrolysable nitrogen in coco-peat.