Previous studies on thermal comfort mainly focus on air-conditioned rooms, whereas passive houses mainly rely on passive technology to ensure comfortable indoor environment. In order to study the thermal environment and the influence of passive technology on thermal comfort of passive houses in winter in cold regions, a passive house in Tianjin area was selected as the research object. The experiment was carried out in two conditions: with heating and without heating. Through indoor environmental test and questionnaire survey, the actual thermal sensation polling value TSV under each working condition was obtained. After data fitting, the TSV model was compared with the PMV model. The original thermal comfort prediction model without heating was modified due to the large deviation of the model. Finally, a thermal comfort evaluation model for passive houses in cold regions was obtained under heating condition and without heating condition. The results show that 44% of the people want the temperature to rise under the condition of no heating. Passive technology alone cannot completely satisfy the thermal comfort requirement of passive housing in cold areas in winter. However, the actual acceptable temperature limit was reduced by 1.93 degrees centigrade under the condition of no heating, suggesting that users are more adaptable to the thermal environment and the transition season can be appropriately extended.