The aim of the study was to investigate the reliability and validity of the timed up & go (TUG) test and the 30-s sit-to-stand (30-s STS) test performed via tele-assessment in ambulatory patients with stroke. Sixty-one patients with chronic stroke were included. For reliability, test-retest and inter-rater reliability were determined. For validity, the correlation coefficient of the values obtained from the face-to-face and tele-assessment procedures of the TUG and 30s-STS tests carried out by the first rater was used. On the first day, the first rater made TUG and 30s-STS tests face-to-face. On the second day, the TUG and 30-s STS were repeated by the first and second raters using the tele-assessment procedure. The tests were applied as tele-assessment 5-7 days later by the first rater to determine the test-retest reliability of the tele-assessment method. ICC for the TUG and 30-s STS tests were 0.998 and 0.992, respectively. The inter-rater agreement between tele-assessments was good for both the TUG test (k = 0.996) and the 30-s STS test (k = 0.981). There was a very strong correlation between tele-assessment and face-to-face assessment of the TUG (r = 0.97) and the 30-s STS test (r = 0.94). The TUG and the 30-s STS tests performed via tele-assessment were reliable and valid for assessing functionality and lower extremity capacity of ambulatory patients with stroke.