Abstract: To improve scaling effect of continuous spring brush scaling machine for freshwater fish, taking sliver carp were as test objects, the effects of scaling roller and operational factors on scaling rate were studied by using a homemade scaling machine. Then the optimal combination of key factors was determined by the orthogonal test, the spring of which were 1.2 mm×16 mm, numbers of spiral-wound spring 2.5 laps, fixed distance of springs 40 mm, rotating speed of scaling roller 1 390 r/min, rotating speed of compression roller 100r/min and rotating speed of transport roller 800 r/min. On this optimal combination the scaling rate mean of silver cap was 68.7%. This study could provide reference for the improvement of continuous spring brush scaling machine for freshwater fish.