| Sri Lanka Railways Class S9 | |
| Manufacturer: | Sifang, China South Locomotive & Rolling Stock Corporation |
| Yearconstruction: | 2000 |
| Yearservice: | 2000 |
| Numberbuilt: | 15 |
| Formation: | 1x SBC, 1x SBD, 4x TC |
| Fleetnumbers: | 849 ~ 863 |
| Operator: | Sri Lanka Railways |
| Depots: | Electrical Power Coaches Shed, Maradana |
| Carlength: | 652NaN2 |
| Maxspeed: | 100km/h |
| Weight: | 73t Engine Compartment Only |
| Engine: | MTU 12V396TC14 |
| Enginetype: | V12 |
| Poweroutput: | 1580HP |
| Transmission: | Diesel-electric |
| Aarwheels: | B-B |
| Brakes: | compressed Air, Dynamic |
| Coupling: | Automatic (dual) |
| Multipleworking: | Yes |
Class S9 is a type of diesel multiple unit train operated by Sri Lanka's state run rail operator Sri Lanka Railways.
S9 DMU was introduced to Sri Lanka in year 2000. This was built by China South Locomotive & Rolling Stock Corporation and this was the first Diesel-Electric multiple unit to run on Sri Lanka rail.
One S9 train-set consists of four Third Class(TC) passenger carriages, 1 Driving Trailer and one Power car with passenger seating. Length of a one car is 65feet. So this one is also capable of higher passenger capacity.
These DMUs are operated on Sri Lanka's Main Line (Up to Rambukkana), Coastal Line, Puttlam Line and Northern Line and not operated in Kelani Valley Line.