Marriage is a legal and lifetime union of two individuals. Unfortunately, some couples failed to fulfill their promises which resulted to separation. In the locality of Santa Fe, Leyte, the total cases of parental separation are two-hundred and twelve (212). Among its barangays, Zone II has the highest incidence. With this, the researchers agreed to uncover the causes of high incidence of parental separation in this barangay. The participants were five separated couples and were selected using purposeful sampling. Further, the study employed qualitative research specifically explanatory case study. The data were obtained thru semi-structured interviews and were analyzed using the thematic analysis. The findings revealed that the causes of high incidence of parental separation in Barangay Zone II, Santa Fe, Leyte are irresponsible behaviors, infidelity, crime-related activities, and change of feelings. Hence, the researchers recommended the local government to formulate programs with the aim of building healthy marriages. Parents must reflect with their actions and value more their marriage. Children with separated parents should read this study to be informed with the causes of parental separation. And the future researchers should utilize this as a basis of identifying the known and still unknown in relation to parental separation.