The Teen Mom 2 regular was arrested and taken into custody alongside her on/off fiance Gary Head in June (12) after a heated altercation.
He was formally accused of beating Evans, while the 20-year-old mum was charged with simple assault. Both youngsters were slapped with charges of possession of marijuana, drug paraphernalia and a controlled substance.
The case returned to court this week, when a judge dropped all four counts against her, reports Eonline.com.
Meanwhile, Head pleaded guilty to a charge of assault on a female as part of a plea deal with prosecutors.
Evans' lucky break emerges days after she was granted a permanent protective order against her ex, banning Head from contacting her for one year.
It is the latest of Evans' legal issues - she was jailed twice in January (12) for violating a restraining order and allegedly threatening her former roommate, and arrested in March (12) on allegations of stalking.