The present invention provides a production method of a
hydroxyl-containing polymer including: protecting a hydroxyl group of a
hydroxyl-containing monomer with a protecting group to make the monomer a
protected monomer with decreased hydrophilicity; adding the protected
monomer alone or together with a hydrophobic monomer to a water-based
medium containing a salt and a dispersion stabilizer; adding a
polymerization initiator to the mixture to carry out suspension
polymerization; and de-protecting the obtained polymer having the
protecting group to recover the hydroxyl group.