Objective: To study tolerance to lactose in milk chocolate among symptomatic lactose maldigesters. Design: Randomized cross-over study. Subjects: Twenty-seven adult lactose maldigesters with symptomatic lactose intolerance. Methods: A 100 g chocolate sample prepared with whole milk (12 g lactose), whole-milk powder (12 g lactose), low-lactose milk powder (2 g lactose) or lactose-free milk powder was eaten after an overnight fast. Gastrointestinal symptoms (flatulence, abdominal bloating, abdominal pain, borgorygmi and nausea) were recorded in a questionnaire during the following 8 h. Bowel movements and stool consistency were also registered during the test day. Results: The numbers of persons reporting different gastrointestinal symptoms or any of the symptoms did not differ significantly after eating the chocolate samples. No statistical differences were found in the estimated strength of the different symptoms or the total strength of all symptoms combined. Differences in the bowel frequency and stool consistency were also non-significant. Conclusions: Lactose malabsorbers with self-reported lactose intolerence did not differ in their response to milk chocolate samples containing different amounts of lactose.