Exhibit
31.2

Rule
13a-14(a)/15d-14(a) Certifications

I, David A.
Curtis, certify that:

1. I have
reviewed this annual report on Form 10-K of FNB Bancorp;

2. Based on my
knowledge, this annual report does not contain any untrue statement of a
material fact or omit to state a material fact necessary to make the statements
made, in light of the circumstances under which such statements were made, not
misleading with respect to the period covered by this report;

3. Based on my
knowledge, the financial statements, and other financial information included
in this report, fairly present in all material respects the financial
condition, results of operations and cash flows of the registrant as of, and
for, the periods presented in this report;

4. The
registrants other certifying officer and I are responsible for establishing
and maintaining disclosure controls and procedures (as defined in Exchange Act
Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting
(as defined in Exchange Act Rules 13a-15(f) and 15d-15(f) for the registrant
and have:

| |    |                                                                                                                                                                                                                                                                                                                                                                                           
| | -- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| | a) | Designed
 such disclosure controls and procedures, or caused such disclosure controls and
 procedures to be designed under our supervision, to ensure that material
 information relating to the registrant, including its consolidated subsidiaries,
 is made known to us by others within those entities, particularly during the
 period in which this annual report is being prepared;
| |    |                                                                                                                                                                                                                                                                                                                                                                                           
| | b) | Designed
 such internal control over financial reporting, or caused such internal
 control over financial reporting to be designed under our supervision, to
 provide reasonable assurance regarding the reliability of financial reporting
 and the preparation of financial statements for external purposes in
 accordance with generally accepted accounting principles;              
| |    |                                                                                                                                                                                                                                                                                                                                                                                           
| | c) | Evaluated
 the effectiveness of the registrants disclosure controls and procedures and presented
 in this report our conclusions about the effectiveness of the disclosure
 controls and procedures, as of the end of the period covered by this report
 based on such evaluation; and                                                                                                   
| |    |                                                                                                                                                                                                                                                                                                                                                                                           
| | d) | Disclosed in
 this report any change in the registrants internal control over financial reporting
 that occurred during the registrants fourth fiscal quarter that has
 materially affected, or is reasonably likely to materially affect, the
 registrants internal control over financial reporting; and                                                                             

5. The
registrants other certifying officer and I have disclosed, based on our most
recent evaluation of internal control over financial reporting, to the
registrants auditors and the audit committee of registrants board of
directors:

| |    |                                                                                                                                                                                                                                                                              
| | -- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| | a) | All
 significant deficiencies and material weaknesses in the design or operation
 of internal control over financial reporting which are reasonably likely to
 adversely affect the registrants ability to record, process, summarize and
 report financial information; and
| |    |                                                                                                                                                                                                                                                                              
| | b) | Any fraud,
 whether or not material, that involves management or other employees who have
 a significant role in the registrants internal control over financial
 reporting.                                                                                                

|                                                   | 
|-------------------------------------------------- | 
|Date: March 13,
 2009.                             | 
|                                                   | 
|/s/ David A.
 Curtis                               | 
|                                                   | 
|David A.
 Curtis                                   | 
|Senior Vice
 President and Chief Financial Officer | 

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