The study objective was to determine reference values of selected biochemical parameters of the haemolymph of Cepaea nemoralis snails (Mollusca, Gastropoda, Helicidae). The study determined the activity of aminotransferases (AST and ALT), which was 11.22 ± 10.92 [u/l] and 6.72 ± 3.18 [u/l], respectively, and alkaline phosphatase (ALP) at a level of 3.92 ± 2.08 [u/l]. The level of amylase (AMY) in the haemolymph was 2.32 ± 0.74 [u/l], while lipase (LIP) was 0.74 ± 0.79 [u/l]. The concentration of urea (UREA) was established at 2.28 ± 0.48 [mg/dl], creatinine (CREA) at 2.28 ± 0.09 [mg/dl], uric acid (UA) at 0.22 ± 0.16 [mg/dl], calcium (Ca) at 21.24 ± 2.4 [mg/dl], and total protein (TP) at 1.38 ± 0.34 [g/l]. The specific gravity of the haemolymph was 1.0 ± 0.002. The haemolymph was obtained from 211 individuals in the active phase collected from their natural habitat. The biochemical parameters of the haemolymph were determined with a BS 180 apparatus (Mindray), and the specific gravity with a refractometer. The article also desrcibes an intravital technique of collecting haemolymph from C. nemoralis. The results obtained may constitute an aid and a guideline for scientists dealing with the physiology of land molluscs.