| Official Name: | South Lansing, New York |
| Settlement Type: | Census-designated place |
| Pushpin Map: | New York#USA |
| Pushpin Label: | South Lansing |
| Coordinates: | 42.5378°N -76.5058°W |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | New York |
| Subdivision Type2: | County |
| Subdivision Name2: | Tompkins |
| Subdivision Type3: | Town |
| Subdivision Name3: | Lansing |
| Area Footnotes: | [1] |
| Area Total Sq Mi: | 2.76 |
| Area Land Sq Mi: | 2.76 |
| Area Water Sq Mi: | 0.00 |
| Area Total Km2: | 7.16 |
| Area Land Km2: | 7.15 |
| Area Water Km2: | 0.01 |
| Population As Of: | 2020 |
| Population Density Km2: | 150.77 |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation Ft: | 842 |
| Postal Code Type: | ZIP Code |
| Postal Code: | 14882 (Lansing) |
| Area Code: | 607 |
| Blank Name: | FIPS code |
| Blank Info: | 36-69342 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 2806984 |
| Population Total: | 1078 |
| Unit Pref: | Imperial |
| Population Density Sq Mi: | 390.44 |
South Lansing is a census-designated place (CDP) in the town of Lansing, Tompkins County, New York, United States. The CDP includes the hamlets of South Lansing, Terpening Corners, and Asbury. The area was first listed as a CDP prior to the 2020 census.
The community is in northern Tompkins County, southeast of the geographic center of the town of Lansing. It is the location of the Lansing Town Hall. New York State Route 34 passes through the community, leading north to Auburn and south through the village of Lansing 7miles to Ithaca. State Route 34B joins Route 34 briefly in South Lansing but heads east 7miles to Route 38 between Groton and Freeville, while to the west it soon turns and runs parallel to Route 34, rejoining it in Fleming.