Kentucky, at the Commonwealth level, does not regulate or license security officers. However, there are major metropolitan areas such as Louisville that do have a structure of regulation. The licensure content discussed within is narrowly directed at this municipality.
Kentucky does regulate and oversee conceal and carry weaponry at the state level.

Fees:
$25 Application fee
$25 Background check fee
$60 CCDW(Concealed Deadly Weapons) Application fee
“Active and retired peace officers that meet the requirements of KRS 237.110(7) are exempt from paying the application or renewal fee.”

See: Application

Louisville Metro Code of Ordinances (LMCO) (B)(2)
The applicant must be at least 21 years of age

LMCO § 124.05(B)(1)
The applicant must be a citizen of the United States

Not required

ARMED:  § 124.05 (F) ARMED SECURITY OFFICER’S LICENSE:

LMCO § 124.05(C)
Applicants shall be required to hold a valid license to carry a concealed deadly weapon (“CCDW”) pursuant to KRS 237.110.  The applicant must provide proof from the Commonwealth of Kentucky that he or she has a valid CCDW, and shall continue to hold such license at all times licensed as an Armed Security Officer.

CCDW is now an ONLINE Process. To carry a concealed deadly weapon, complete the application process at: Concealed Carry Licensing Portal

§ 124.02 (D)  At all times while on duty or otherwise working as an armed security officer, every armed security officer shall carry a valid license, and such license shall be subject to inspection by any police officer or by any other person designated by the Director.

LMCO § 124.05(A)(3)(d)
An applicant shall not have been convicted of or currently under indictment for any of the following:  a felony; illegally using, carrying or possessing a deadly weapon as defined in KRS 500.080(4); impersonation of a law enforcement officer or employee of the United States or any political subdivision thereof; the illegal use, sale or possession of a controlled substance as defined in KRS Chapter 218A; or any crime of moral turpitude.

Not listed

LMCO § 124.05(A)(3)(f)
An applicant shall  have not been hospitalized for drug or alcohol abuse treatment within the past two years, and if so hospitalized, will provide a written statement from a licensed and qualified physician or clinical psychologist verifying that he or she is mentally and emotionally fit for the duties of an armed security officer.

LMCO § 124.05(A)(3)(e)

An applicant shall have not been adjudged mentally incompetent or currently under charge thereof, by a federal court or court of any state or political subdivision, and shall have not been hospitalized for psychiatric treatment within the past two years, and if so hospitalized, will provide a written statement from a licensed and qualified physician or clinical psychologist verifying that he or she is mentally and emotionally fit for the duties of an armed security officer;

An application must include an affidavit certfying that e that there is no pending, nor has there ever been a mental inquest taken out against . I further state that there is not now pending nor
has there ever been any action challenging his/her mental competency.

700 West Jefferson Street
Louisville, KY 40202
Attn: Disability/Mental Inquest

Telephone: (502) 595-3261 / After hours: (502) 595-4587
Hours: 8:30 am to 4:30 pm

LMCO § 124.05(A)(3)(d)
An applicant shall not have been convicted of or currently under indictment for any of the following:  a felony; illegally using, carrying or possessing a deadly weapon as defined in KRS 500.080(4); impersonation of a law enforcement officer or employee of the United States or any political subdivision thereof; the illegal use, sale or possession of a controlled substance as defined in KRS Chapter 218A; or any crime of moral turpitude. An applicant shall have satisfied this requirement, if in those instances where the foregoing offense was a misdemeanor, conviction occurred at least two years prior to application for the license; or, in those instances where the offense was a felony, the applicant has been granted a pardon or has had his or her civil rights restored and has been specifically authorized to possess a firearm by means of relief granted by the United States Secretary of the Treasury pursuant to the Federal Gun Control Act of 1960, as amended;

Not Required