I haven't had a chance to go measure the shoulder strap just yet but I believe that it is at least 12 to 15 inches long which means it can fit on your shoulder as long as your upper arm is it too big
To clarify this bag can be used as a shoulder bag, the strap is not very long so when you do put it on the purse will actually be underneath your arm about where your elbow is. Otherwise it can be considered a handbag that can be worn at the elbow, but you can push it all the way up over your shoulder.
Okay so I finally got a chance to go check on what the length is of the purse strap the length is 20 inches and there is plenty room regardless how tall or how big you are for this person to bring it all way up to your shoulder.