When i put my baby on tummy time she throws up, she is 4 month. ?

Close to feeds?: It may be as simple as changing the schedule. Try giving her tummy time prior to feeds and not after. Many babies have a bit of reflux at this age.

Could be reflux: You should bring your daughter to see her pediatrician. Gerd (gastro-esophageal reflux) can present in many ways, including frequent spitting up/vomiting, worse when laying down. There are many non-medication helpful hints (thickened feeds, maintaining an upright position after feeding, elevating the head of the crib, frequent burping), as well as prescription meds, but first we need a diagnosis.

Likely normal spitup: I would try to do tummy time at a time that she doesn't have a full tummy. Tummy time is important so don't give up.

REFLUX: Spit up or reflux increases if placing pressure on abdomen when stomach is full. Babies need lots of tummy time to increase muscle strength and avoid head flattening. To avoid spit up first burp every 5 min during breast feed, for 30 sec each, or burp every 1/2 to 1 oz if formua fed, then keep upright after feeds for 20 min. Then try tummy time. Or try tummy time for the 30 min before next fee.