Can ca represent client in itat or is it only llb's who can

Yes....CAs can appear till tribunal level.

Originally posted by : Mohit
	I mean is it written like in some section of Income Tax Act or something...

As per Rule 2(ii)(a) of the Income-tax (Appellate Tribunal) Rules, 1963, in relation to an assessee, 'authorised representative' means a person duly authorised by the assessee under section 288 to attend before the Tribunal.
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A 'Chartered Accountant' is covered as an 'authorised representative' under section 288(2)(iv) of the Income-tax Act, 1961.