Smart Grid, Regarded As The Next Generation Power Grid, Uses Two-way Flows Of Electricity And Information To Create A Widely Distributed Automated Energy Delivery Network. In This Work We Present Our Vision On Smart Grid From The Perspective Of Wireless Communications And Networking Technologies. We Present Wireless Communication And Networking Paradigms For Four Typical Scenarios In The Future Smart Grid And Also Point Out The Research Challenges Of The Wireless Communication And Networking Technologies Used In Smart Grid.