Purpose: Quality of life is the cornerstone of palliative care, and assessing it requires validated and standardized questionnaires. However, the majority of questionnaires are not tested in a hospice setting. The purpose of this study is to evaluate the quality of life in a hospice using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 15 for Palliative Care (PAL) (EORTC QLQ-C15-PAL) questionnaire and validating it in Croatian language. Methods: The study was conducted prospectively on 151 consecutive patients who were evaluated at the admittance to the hospice and after 7 days. Along with the EORTC QLQ-C15-PAL, both evaluations included the Edmonton Symptom Assessment System (ESAS) and the Palliative Performance Score (PPS) version 2. Cronbach a coefficient was used to test the reliability of multi-item scales, while construct and concurrent validity was tested using the Pearson correlation coefficients. Known-group validity was evaluated using the Student t test. Results: Physical functioning, pain, and emotional functioning scales all exhibited high reliability on both assessments and met the criteria of Cronbach alpha .70, while fatigue scale met the predetermined criteria in the follow-up assessment C. alpha = .90). Adequate validity was also displayed, with the highest correlation coefficients between the EORTC QLQC15-PAL and ESAS scales recorded for the corresponding items. The EORTC QLQ-C15-PAL was also able to distinguish patients with different PPS scores, exhibiting excellent clinical validity. Conclusions: The EORTC QLQ-C15-PAL can be used successfully in Croatian palliative care. However, inevitable issues such as low retest percentage due to short survival and low physical functioning scores need to be acknowledged in further formulations of quality of life questionnaires specific to hospice care.