A bicycle training stand for engaging an axle of a bicycle wheel, comprising: a frame having an axle bore and a perforation at least an end thereof, wherein the perforation is communicated with the axle bore; a first clamping unit and a second clamping unit provided on the frame to engage opposite ends of the axle; wherein the first clamping unit comprises: an abutting member fitted in the axle bore of the frame, wherein the abutting member is movable in an axial direction of the axle bore, and has an abutting end to contact the axle of the bicycle wheel; an operation member pivotally provided on the frame, wherein the operation member is movable between a first position and a second position, and has a contacting portion which goes through the perforation; when the operation member is at the first position, the contacting portion presses the abutting member to confine a position of the abutting member; when the operation member is at the second position, the contacting portion has no contact with the abutting member; wherein the abutting member of the first clamping unit has a rack thereon, and the contacting portion of the operation member has teeth to be meshed with the rack of the abutting member when the operation member is at the first position; wherein the first clamping unit includes an adjusting member which has a threaded rod, and the abutting member includes an abutting shaft and a sleeve, wherein the sleeve is open at opposite ends thereof for receiving the abutting shaft therein; the rack is provided on an outer surface of the sleeve; the abutting shaft has a threaded hole for screwing in an end of the threaded rod of the adjusting member. a frame having an axle bore and a perforation at least an end thereof, wherein the perforation is communicated with the axle bore; a first clamping unit and a second clamping unit provided on the frame to engage opposite ends of the axle; wherein the first clamping unit comprises: an abutting member fitted in the axle bore of the frame, wherein the abutting member is movable in an axial direction of the axle bore, and has an abutting end to contact the axle of the bicycle wheel; an operation member pivotally provided on the frame, wherein the operation member is movable between a first position and a second position, and has a contacting portion which goes through the perforation; when the operation member is at the first position, the contacting portion presses the abutting member to confine a position of the abutting member; when the operation member is at the second position, the contacting portion has no contact with the abutting member; wherein the abutting member of the first clamping unit has a rack thereon, and the contacting portion of the operation member has teeth to be meshed with the rack of the abutting member when the operation member is at the first position; wherein the first clamping unit includes an adjusting member which has a threaded rod, and the abutting member includes an abutting shaft and a sleeve, wherein the sleeve is open at opposite ends thereof for receiving the abutting shaft therein; the rack is provided on an outer surface of the sleeve; the abutting shaft has a threaded hole for screwing in an end of the threaded rod of the adjusting member. an abutting member fitted in the axle bore of the frame, wherein the abutting member is movable in an axial direction of the axle bore, and has an abutting end to contact the axle of the bicycle wheel; an operation member pivotally provided on the frame, wherein the operation member is movable between a first position and a second position, and has a contacting portion which goes through the perforation; when the operation member is at the first position, the contacting portion presses the abutting member to confine a position of the abutting member; when the operation member is at the second position, the contacting portion has no contact with the abutting member; wherein the abutting member of the first clamping unit has a rack thereon, and the contacting portion of the operation member has teeth to be meshed with the rack of the abutting member when the operation member is at the first position; wherein the first clamping unit includes an adjusting member which has a threaded rod, and the abutting member includes an abutting shaft and a sleeve, wherein the sleeve is open at opposite ends thereof for receiving the abutting shaft therein; the rack is provided on an outer surface of the sleeve; the abutting shaft has a threaded hole for screwing in an end of the threaded rod of the adjusting member.