Here is the eligibility criteria for SBI Bank PO exam

Eligibility criteria (as on 28/02/2010)

Essential academic qualifications: General
category and others category - 60% aggregate marks in XIIth standard or
in Diploma after Xth standard; and 55% aggregate marks in Graduation.
SC/ST/PWD category - 55% aggregate marks in XIIth standard or in
Diploma after Xth standard; and 50% aggregate marks in Graduation. In
case of candidates having professional qualification(s) of CA or CWA or
CFA or CS (company secretary), where graduation is not compulsory, the
General and others category candidates should have secured minimum 60%
aggregate marks in XIIth standard or Diploma (55% in case of SC/ST/PWD
candidates) and pass marks in above examination(s).

Graduate
Candidates who have not passed XIIth standard examination but have
passed diploma course after Xth standard with 60% aggregate marks (55%
for SC/ ST/PWD) are eligible for the captioned recruitment, provided
(a) Diploma course passed must be a minimum of two years duration full
time course (diploma course through correspondence are not eligible)
(b) Diploma course should be recognized/ approved by the state board of
technical education of the concerned state /UT.

The
percentage of marks in XIIth std./diploma course/ graduation shall be
arrived at by dividing the marks obtained by the candidate in all the
subjects by aggregate maximum marks of all subjects irrespective of
optional/ additional optional subjects studied. Similarly percentage of
marks in graduation shall be arrived at by dividing the aggregate of
marks obtained by the candidate in all subjects by maximum marks of the
all subjects of course (both for Pass/ Honour course) for all the years
of the course.

Where the candidates have
been awarded cumulative grade point average scores (CGPA scores) or
overall grade point average scores (OGPA scores) or any other kind of
grades in their results, they will have to produce a certificate from
the registrar/ controller of examination / Institute indicating the
equivalent of percentage marks obtained by them.

Age limit as on 28.02.2010

POs - Not
below 21 years and not above 30 years as on 28.02.2010 i.e. candidates
must have been born not earlier than 01.03.1980 and not later than
28.02.1989 (both days inclusive)

POs (RB) - Not
below 21 years and not above 30 years as on 28.02.2010 i.e. candidates
must have been born not earlier than 01.03.1980 and not later than
28.02.1989 (both days inclusive). In case of candidates who have worked
in scheduled commercial bank(s) in the field of Agriculture/Rural
business, the upper age will be relaxed by the completed number of
years of experience of the candidates, subject to maximum of 5 years.

Relaxation in the upper age limit to reserved category candidates: 3
years in the case of OBC candidates (ii) 5 years in the case of
SC/ST/Ex-servicemen (iii) 10 years for VH/OH (Gen); 13 years for VH/OH
(OBC) and 15 years for VH/OH (SC/ST) candidates

most of the banks are having the same criteria as far as percentage of marks is concerned in graduation but it may differ a little bit for more information about other bank PO exam you can go through the link given below

Bank Po Exam Notification

PO Exam CDs