Hollie Hanson, 17, was parked up on the scooter at Westfield Road, Hemsworth, close to the junction with Mayfair Place, when the men approached her from behind.
She said: “Someone grabbed me, covered up my eyes and pulled me to the floor.
“I was really distressed and upset. One man gave me a kicking on the floor and another joined in.
“By the time I got up and rang 999, they had managed to get away with the scooter. I was very shaken.”
Hollie, who used money given to her by her late grandmother to buy the scooter, was left with facial injuries.
She said: “How someone could be so callous and heartless to grab someone from behind and then do this.
“It’s not just a scooter to me. My grandma left me some money when she died and I used it to buy the scooter.
“It has real sentimental value and I can’t believe someone would take it from me.”
Police said the incident took place at around 4.25pm on Monday, April 4.
Both men were wearing dark tops, and one had blue jogging bottoms.
Detective Inspector Dan Tillett of Wakefield District CID said: “Police are appealing for witnesses to this incident in which two men have committed a nasty and quite frankly, cowardly assault on a lone female teenager.
“She showed bravery in resisting these men, and was left with facial injuries after being punched by one of them.”
The moped was later recovered but was being held by police as part of their investigations. Anyone with information is asked to call Wakefield CID on 101.