This psychometric study aimed at assessing the test-retest reliability and criterion-related validity of the V-Sit and Reach (VS) and Toe-Touch (TT) tests when performed by preschoolers. Out of an initial sample of 158 participants 132 performed the tests on three occasions with a week interval. Construct validity was assessed by means of the passive straight leg raise (PSLR) test. Both tests showed excellent reliability (ICC=0.91-0.93 for the VS; ICC=0.93-0.97 for the TT). Statistically significant correlations (p<0.05) were observed between both tests and the PSLR test for all of the groups that were analyzed, except for the TT in the case of three-year old group. In conclusion, these findings indicate that both the VS and the TT are reliable tests that show moderate criterion-related validity for assessing lower-body flexibility in preschoolers. The VS may be a preferable test over the TT.