Are you talking about the rubber hoses or the metal brake lines? Ron assumed the rubber hoses and I'll do the same. I cut the hose with snips first. Then I can get a closed end wrench on the fittings on both ends to get the best grip I can. I feel that gives me the best chance of getting it off without potential damage due to a tight fitting twisting the metal line off. Some folks use heat. Some bathe it in penetrating oil.

Len