Depends on the type of Mutual Fund you have, investment in certain mutual funds for tax saving purpose is called equity linked saving schemes which qualifies for Section 80C deduction. Not all mutual funds can provide 80C deduction. Some common examples of ELSS are–SBI Magnum Tax Gain, HDFC Tax Saver, Fidelity Tax Advantage, Franklin India Index Tax Fund, etc.
If you have SIP Let assume you are investing 2000Per month you claim a deduction of rupees during the year 2000×12month = 24,000 if you are investing regularly during the year.