| Cabinet Name: | Second Smuts Cabinet |
| Cabinet Number: | 4th |
| Jurisdiction: | the Union of South Africa (since the 1909 South Africa Act) |
| Flag: | Red Ensign of South Africa (1912–1951).svg |
| Flag Border: | true |
| Incumbent: | 1921–1924 |
| State Head Title: | Monarch |
| State Head: | King George V |
| Governor General Title: | Governor-General |
| Government Head Title: | Prime Minister |
| Government Head: | Jan Smuts |
| Political Party: | South African Party |
| Legislature Status: | Majority |
| Opposition Party: | National Party |
| Opposition Leader: | Barry Hertzog |
| Election: | 1921 election |
| Previous: | Smuts I |
| Successor: | Hertzog I |