| Serayu | |
| Type: | Inter-city rail |
| Status: | Operating |
| Locale: | West Java, Indonesia |
| Operator: | Kereta Api Indonesia Operational Area 5 Purwokerto |
| Stops: | 18 |
| End: | , Jakarta |
| Distance: | 417km (259miles) |
| Frequency: | Daily each way |
| Trainnumber: | 301-308 |
| Class: | Economy class only |
| Access: | Restricted due to age of rolling stock |
| Seating: | Bus style (3-2) |
| Catering: | On-board café |
| Baggage: | Overhead racks, baggage carriage |
| Speed: | 60–90 km/h |
| Map State: | collapsed |
Serayu is an economy-class train running twice a day between and via,, Tasikmalaya,, Cimahi and Purwakarta. The train was previously known as Cepat Sidareja, Cipuja, and Citrajaya. The name Serayu is derived from the Serayu River, which the train crosses twice on its journey.
Initially called Cepat Sidareja at its inauguration in 1985, the morning train was later renamed to Cipuja, while its night train counterpart was named Citrajaya and the route was extended to and Jakarta. The train Galuh called at stations on this route which were skipped by both Cipuja and Citrajaya. In the early 2000s, Cipuja and Citrajaya were rebranded to Serayu. In 2013, the route was extended to Purwokerto.
The Serayu train runs four times daily, twice per direction, following the route –––––––––––––.