Authorities say 26-year-old Pablo Ansurez Sanchez was one of several people inside the Lancaster apartment when police were called early Friday.
An officer found the body of the woman in the basement, where authorities allege Sanchez and the victim got into an argument and he ended up choking her.
Lancaster County Coroner Dr. Stephen Diamantoni says an autopsy will be done Monday.
District Attorney Craig Stedman says the victim has not yet been identified.
Sanchez was arraigned and taken to Lancaster County Prison without bail. A listed number for him could not be found Saturday and it was unclear whether he had an attorney.