EXHIBIT
31.2

Certifications
under Section 302 of the Sarbanes-Oxley Act of 2002

I, Mitchell A. Derenzo, certify
that:

| | 1. | I
                                         have reviewed this quarterly report on Form 10-Q/A of American River Bankshares;
| | -- | ---------------------------------------------------------------------------------------------------------------------------

| | 2. | Based
                                         on my knowledge, this 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(s) 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 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
most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) 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(s) 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 the registrant’s board of directors (or persons
                                         performing the equivalent functions):
| | -- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

(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: November 7, 2018                               | 
|---------------------------------------------------- | 
|                                                     | 
|By: /s/ MITCHELL A. DERENZO                          | 
|Executive Vice President and Chief Financial Officer | 

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