Koiwagawa Station (小岩川駅, Koiwagawa-eki) is a railway station in the city of Tsuruoka, Yamagata, Japan, operated by East Japan Railway Company (JR East).

Koiwagawa Station is served by the Uetsu Main Line, and is located 105.4 kilometres (65.5 mi) from the terminus of the line at Niitsu Station.

The station has two opposed side platforms connected to the station building by a footbridge. The station is unattended.

1	■ Uetsu Main Line	for Tsuruoka, Atsumi Onsen, and Sakata
2	■ Uetsu Main Line	for Niitsu and Murakami

Koiwagawa Station opened on February 1, 1950. With the privatization of JNR on April 1, 1987, the station came under the control of JR East.

• National Route 7
• Koiwagawa Post Office

• List of railway stations in Japan

Media related to Koiwagawa Station at Wikimedia Commons

• JR East Station information (in Japanese)