Yes you can apply for admission in Bachelor of computer application course after passing three year polytechnic courses . here I am giving you information about admission in BCA course below :

BCA Eligibility:
You have to passed 12th grade examination from CBSE or equivalent board with English. You must have minimum 50% marks in aggregate.
Or
The applicant should have three year diploma in a branch of Engineering from a polytechnic Institutes/University approved by AICTE.

Some best BCA Colleges in India
Christ University
Hosur Road, Bangalore
080-40129100/ 40129600

Madras Christian College
Velachery Main Road, East Tambaram, Chennai
044-22390675

Institute of Management Studies
A-8B, IMS Campus, Sector-62, Noida
0120-4798800/02

Department of Computer Applications, SRM University
3 Veerasamy Street, West Mambalam, Chennai
044-24742836/24747231

Women Christian College
No. 51, College Road, Nuhgambakkam, Chennai 044-28275926/ 2823 1676

University College-Kurukshetra
Kurukshetra 01744-238169
DAV College Sector 10, Chandigarh 0172-2742854

Xavier Institute of Computer Application
Campus Navrangpura, P.B. No. 4168, Ahmedabad 079-26308057

Maharani Laxmi Ammanni College For Women
Post, Malleswaram 18th Cross, Bangalore 080-23349311

St. Xavier College P.O. Box No. 32, Mapusa, Goa
0832-2262356/2250705