In a juvenile delinquency proceeding pursuant to Family Court Act article 3, the appeal is from an order of the Family Court, Kings County (Bogacz, J.), dated September 10, 1996, which extended the juvenile’s placement with the Division for Youth for a period of 12 months commencing June 28, 1996.
Ordered that the order is reversed, on the law, without costs or disbursements, and the petition is dismissed.
The appellant’s period of placement with the Division for Youth (hereinafter DFY) was to expire on June 28, 1996. Prior to that date DFY timely petitioned the Family Court for an extension of placement. On May 29, 1996, when the petition first came on for a hearing, the Family Court adjourned the matter to July 18, 1996, and issued a temporary order of exten*533sion for the period from June 28, 1996, to July 18, 1996. On July 18, 1996, the court again adjourned the matter, apparently with the consent of the Law Guardian, to September 10, 1996, and issued an order extending placement from July 18, 1996, to September 10, 1996.
After a hearing on September 10, 1996, the Family Court granted the petition, and extended placement for twelve months, effective June 28, 1996. Thus, the period of placement expired on June 28, 1997. On April 27, 1997, DFY released the appellant to his parents’ custody and placed him in aftercare. However, on April 28, 1997, DFY filed a petition seeking extension of the appellant’s placement for six months, from June 28, 1997, to December 28, 1997.
By failing to decide the petition for extension of placement within 45 days of the expiration of the original placement, as mandated by Family Court Act § 355.3 (5), the Family Court lost jurisdiction over the appellant and the petition must be dismissed. Mangano, P. J., Copertino, Altman and Goldstein, JJ., concur.