Background Dropout in youth psychotherapy is high, especially for ethnic minority patients. An important determinant of dropout is the quality of the therapeutic relationship. This study evaluated the association between the therapeutic relationship and dropout in therapy with ethnic minority youth. Method Our study was done in a community youth mental health care institution. Seventy patients were included who were dropouts or completers of psychotherapy. The therapeutic relationship was measured with an instrument (i.e., the Child version of the Session Rating Scale (C‐SRS)) that was completed each session by the patient. For each patient, the treatment termination status (dropout or completer) was indicated. A General Estimation Equation (GEE) was conducted to indicate whether the course of total C‐SRS scores during therapy differed for dropouts and completers. Results The course of the scores differed significantly between dropouts and completers. Both groups started with similar scores, but on average, the scores of dropouts decreased during therapy, while the scores of completers increased. Conclusions Our results indicate that if there is a drop in the rated quality of the therapeutic relationship (i.e., monitor the difference between the present C‐SRS score with the previous scores), the therapist should communicate this with the patient. This could lead to an improvement of the therapeutic relationship and a decrease in dropout.