 This is a double-blind, randomised, controlled, two-period crossover phase Ib trial using an individualised standard meal with a fixed nutrient ratio in subjects with type 2 diabetes mellitus to investigate post-prandial blood glucose control with BioChaperone insulin lispro compared to insulin lispro Humalog, Eli Lilly and Company before and after a period of multiple daily dose administrations for 14 days. Each subject will be randomised to a sequence of two treatments, either BioChaperone insulin lispro-Humalog or Humalog-BioChaperone insulin lispro. Injections will take place immediately before an individualised standard meal in the morning of day 1, 2, 13, and 14. Insulin doses will be determined at the screening visit. During the outpatient phase the subjects will keep their basal insulin constant except changes for safety reason. They will self-measure blood glucose at least 4 times daily pre-prandial and at bedtime. In addition, on two days per outpatient period Day 5 and 9 blood glucose will be measured 7 times daily pre-prandial, 2 hours post-prandial and at bedtime. 