U-ka saegusa IN db IV ~Crystal na Kisetsu ni Miserarete~ is the fourth and last studio album by Japanese group U-ka Saegusa in dB.

[1] The album includes 5 previously released singles since Yukidoke no Ano Kawa no Nagare no You ni till Natsu no Owari ni Anata he no Tegami Kakitometeimasu.

The album was released on November 25, 2009 under Giza Studio label.

The album reached #33 rank in Oricon for first week.

It charted for 2 weeks and totally sold 5,999 copies.