1. A method for producing a sugar liquid, the method
comprising the steps of:
(A) reacting mannanase with a liquid component obtained by hydrolysis treatment of woody biomass to obtain a saccharified liquid; and
(B) filtering the saccharified liquid in Step (A) through a microfiltration membrane and/or ultrafiltration membrane to collect a sugar liquid from the permeate side.

2. The method for producing a sugar liquid according to claim 1, wherein the woody biomass is coniferous biomass.
3. The method for producing a sugar liquid according to claim 1 or claim 2, wherein the hydrolysis treatment in Step (A) is one or more selected from the group consisting of hydrothermal treatment, steam explosion treatment, and dilute acid treatment.
4. The method for producing a sugar liquid according to any one of claims 1 to 3, wherein, in the Step (A), cellulase is reacted with the liquid component.
5. The method for producing a sugar liquid according to any one of claims 1 to 4, wherein, in Step (A), the amount of mannanase added is not less than 0.01 Unit/g with respect to the total amount of mannose (g) contained in the liquid component.
6. The method for producing a sugar liquid according to any one of claims 1 to 5, wherein a functional surface(s) of a material(s) of the microfiltration membrane and/or ultrafiltration membrane in Step (B) is/are an organic membrane(s)
7. The method for producing a sugar liquid according to any one of claims 1 to 6, wherein the microfiltration membrane in Step (B) is a microfiltration membrane having an average pore size of 0.01 to 0.5 urn.
8. The method for producing a sugar liquid according to any one of claims 1 to 7, wherein the ultrafiltration membrane in Step (B) is an ultrafiltration membrane having a molecular

weight cutoff of 5000 to 150,000.
9. The method for producing a sugar liquid according to any
one of claims 1 to 8, comprising the step of:
(C) filtering the sugar liquid obtained in Step (B) through an ultrafiltration membrane having a molecular weight cutoff of 300 to 1000, to collect a sugar liquid containing mannobiose and/or mannotriose from the feed side, and to collect a sugar liquid containing a monosaccharide from the permeate side.
10. A method for producing a sugar liquid, the method
comprising, in the method for producing a sugar liquid
according to any one of claims 1 to 9, the steps of:
carrying out ultrafiltration membrane treatment as Step (B); and
carrying out Step (A) using an enzyme component(s) collected from the feed side of the ultrafiltration membrane.