"O you who believe! Spend of the good things which you (legally) earned, and of that which We have produced from the earth for you..." (Al-Baqarah: Verse 267)
See more Quranic verses on Zakat and Charity here.
"(The superstructure of) Islam is raised on five (pillars): to utter an attestation of faith, performance of prayer, payment of Zakat, fast of Ramadan and pilgrimage (to Makkah)." (Narrated by Ibnu Umar R.A.)