Official trial is a single, open label, self-controlled, three-period, dose escalation, period fasting single oral administration trial. 12 chinese healthy adult subject met the inclusion criteria 12 people, each gender in half. Each subject first pass 7 days of run-in period, to eliminate the residual substances in food L-carnitine, stable baseline level of endogenous L-carnitine class substance within the subject; at day 4 was baseline sampling point, tno medication but water intake; at day 8 (1st period day 1) fasting oral propionyl L-carnitine hydrochloride tablets 1g; at day 12 (2nd period of day 1) fasting oral hydrochloride propionyl L-carnitine tablets 2g; the first 16 days (3rd period day 1) fasting oral propionyl L-carnitine hydrochloride tablets 4g.Throughout the trial period, control the subjects' diet, eating only allowed as far as possible food without substance L-carnitine class and drink boiled water,diet at sampling day 4, 8, 12, 16 need to be fixed consistently. Every 4 days of dosing interval washout period.