Catching performance of a mechanized pollock longline system compared with traditional one were examined in order to evaluate the practicality during two cruises in the Sokcho area. Mechanized longline system consists of random baiter, bait cutting machine, storage rails, and line hauler. Baiting efficiency of random baiter was 90-95% with 4-5kt shooting speed. Catching performance of the first experiment, salted sand lance only used as a bait. shows no significant difference between mechanized operation with use fresh sand lance as a bait caught significantly more pollock than traditional one with use salted sand lance (P<0.016). Improved catch rates were about 2 times. As soak time goes on, relative catching efficiency shows a steady increase up to 6~7 hours and thereafter gradually decrease.