Imeglimin hydrochloride is a novel oral antidiabetic agent used to treat type 2 diabetes mellitus. Tablet splitting and crushing are occasionally required in clinical practice to facilitate medication administration; however, their effects on the pharmaceutical performance of imeglimin tablets remain unclear. This study evaluated the effects of tablet splitting and crushing on the in vitro dissolution characteristics of imeglimin hydrochloride tablets. Dissolution testing was performed using intact, halved (0.5 tablet × 2), and crushed 500 mg tablets under conditions consistent with the Japanese Pharmacopoeia. The paddle method (50 rpm, 900 mL, 37.0 ± 0.5°C) was used with the first fluid (pH 1.2), the second fluid (pH 6.8), and purified water. Samples were collected at 5, 10, 15, 30, and 45 min, and imeglimin concentrations were determined spectrophotometrically at 245 nm. All experiments were performed in quintuplicate. Crushed tablets showed significantly higher percentages dissolved than intact and halved tablets at 5 and 10 min in all dissolution media. However, the dissolution profiles converged over time, and all preparations achieved nearly complete drug dissolution within 30 min under all test conditions. The powder weight recovery after crushing was 98.7 ± 1.5%, indicating that the physical loss of tablet material during the crushing and recovery procedures was small. These findings indicate that tablet crushing significantly increased the percentage dissolved during the early phase of dissolution but did not affect the final extent of dissolution under the experimental conditions used. Further studies should evaluate the effects of tablet manipulation on pharmacokinetics and clinical outcomes.