The invention discloses a method for producing L-
ornithine by an
immobilized enzyme method, which comprises the following steps: (1) inoculating a seed solution of a human recombinant
arginase I producing strain into a
fermentation culture medium for
fermentation culture, cooling, adding IPTG (
isopropyl-beta-d-thiogalactoside) into the
system, and performing induced culture for 20-28 hours; (2) carrying out bacterium breaking treatment on the culture solution subjected to induced culture, passing through a
ceramic membrane, and collecting filtrate; hanging the filtrate on a column; and (3) enabling a substrate solution containing L-
arginine to flow through the
nickel column with the hung column for
biotransformation, and collecting an
effluent transformation solution, so as to produce L-
ornithine. According to the invention, a novel human recombinant
arginase I producing strain is firstly constructed, and a
fermentation process is optimized, so that the yield and
enzyme activity of the human recombinant
arginase I are improved; then carrying out immobilization treatment on the human recombinant arginase I produced by fermentation by adopting a
nickel column hanging column; and then a substrate solution is fed for conversion treatment, so that the L-
ornithine is produced by the
immobilized enzyme method, and the conversion rate is increased.