The purpose of this study was to analyze the factors enhancing stability of multicultural marriages in Finland. The main question set for the study was: What factors explain the stability of multicultural marriages described by the spouses themselves? This was further divided into two sub-questions of what phases long-lasting multicultural marriages go through and what the special features describing the stability of multicultural marriages are. This was a qualitative study, in which 11 Finnish spouses’ interviews formed the data. The results describe the phases of a long-lasting multicultural marriage and factors enhancing the stability of a multicultural marriage, based on which the stability of multicultural marriages was further discussed. The possible conflicts and supportive factors can be located at various levels each contributing to the quality of the relationship. The accumulation theory of multicultural relationships is introduced as the conclusion.