We examined biochemically the distribution of lysosomal enzyme activities in the ocular tissues and adnexa of albino rabbits using p-nitrophenyl derivatives. The pink and white lobes of Harderian gland disclosed the highest specific activities of acid phosphatase, N-acetyl-beta-D-glucosaminidase, and alpha-L-fucosidase. The lacrimal gland showed moderately high specific activities of acid phosphatase and N-acetyl-beta-D-glucosaminidase. The optic nerve, brain, ciliary body plus iris, and retina plus choroid exhibited nearly the same specific enzyme activities. The tear fluids showed higher lysosomal enzyme activities than did the serum. To our knowledge, this is the first reported measurement of lysosomal enzymes in Harderian gland, lacrimal gland, and optic nerve of the rabbit.