As per my searching I was founded that the IIt Delhi is does not accepting candidates by GMAT. Only CAT scores are accepted by IIT Delhi for MBA admission.

Candidates are needed to attend CAT entrance exam for MBA admission.

Eligibility:
Candidates have a Bachelor's Degree or equivalent awarded by any of the universities incorporated by an act of the central or state legislature in India or other educational institutions established by an act of Parliament

A minimum of 60% marks in aggregate (of all the years/semesters) or 6.75 CGPA on a 10 point scale or equivalent in the qualifying degree.

Fee:

Tuition Fees for Indian Citizen:
Rs. 4 Lacs for the entire MBA Full Time Programme payable in equal installments (4 Semesters)
Foreign National Students (Self-Financing):
Following are the fees per semester, chargeable from Self-Financing Foreign National

Student including those seeking admission as visting students:
US $ 1,000 and INR 10,435 for SAARC Countries
US $ 2,000 and INR 10,435 for Other Countries

Important Dates for MBA:

CAT Result Announcement
2nd Week of January 2016

Online Submission of Application Form begins on
Next day of CAT 2015 result declaration

Last Date for receipt of Print copy of Application Form alongwith Demand Draft
29 January 2016 (Friday)

Group Discussion & Personal Interview (will be held at IIT Delhi)
10-13 March 2016 (Thursday to Sunday)

Declaration of Admission Results
02 May 2016 (Monday)

New Students to report to allotted hostel
21 July 2016 (Thursday)

Orientation and Registration for New Students
22-23 July 2016 (Friday-Saturday)

Classes begin
25 July 2016 (Monday)

Contact to:

Department of Management Studies,
IV Floor, Vishwakarma Bhavan,
IIT Delhi, Saheed Jeet Singh Marg,
Hauz Khas, New Delhi - 110016