60+ Years of

trusted since 1997

Altadena, San Marino, and Sierra Madre's Private Security Experts

At Guardian National Security, we are dedicated to our customers’ safety and have experience working at businesses, shopping centers, schools, gated communities, hotels, manufacturing facilities, recreational areas, museums, and many other residential, commercial and industrial locations throughout Altadena, San Marino, Sierra Madre, and the surrounding area. 

Count on Guardian National Security for any of the following security services:

  • Standing guard service
  • Alarm response
  • Event security
  • Fire watch
  • Foot, bike and golf cart patrol
  • Lobby/reception guards
  • Lock up and alarm
  • Logistical services
  • Vehicle patrol
  • Wireless security equipment

Serving All of Los Angeles County, CA

Professional &

Security Guard Services


We specialize in developing security strategies that effectively reduce theft, vandalism, trespassing, employee pilferage, and other criminal activity in retail stores, malls, and shopping centers. »


Whether you need nightly lock-up and alarm services, parking lot patrol, or temporary fire watch services, we have the skills and expertise to provide a cost-effective security solution to meet your priorities. »


Our highly trained and licensed guards can be trusted to keep valuable machinery and equipment secure or to protect against vandalism, graffiti, trespassing, and other unwanted activity. »


Guardian National Security is thoroughly prepared to provide a wide range of transportation and logistical security duties for your trucking company, loading dock, or rail yard. »


We’re proud to provide unparalleled security guard services for homeowner associations, gated communities, apartment complexes, condominiums, and communities of all sizes.


Our Process

At Guardian National Security, we are committed to providing individually-tailored security plans to every customer at an affordable cost. In order to best serve the unique needs of our clients, we have developed an efficient multi-step process for designing, implementing, and monitoring custom security plans.

Free Consultation


We will thoroughly discuss your security needs and concerns in order to understand your property.

Proposal & Quotes


We guarantee to match or beat any competitor’s quote for the same services.

On-Site Follow Up


One of our security advisors will complete a thorough on-site walk-through at your location.

Customized Security & Patrol Plans


We will delineate patrol routes, schedules & post orders based on your specific needs.

Guards to Arrive On-Time, In Uniform & Ready to Work


You can expect your assigned guards to arrive on-time, in uniform, and ready to work.

Daily Activity Reports, Incident Reports & Parking Violation Warnings


We provide clients with daily activity reports, incident reports, and parking violation warnings.

Protecting California's Most Recognized Brands

Brookstone Logo Burger King Logo Kohl’s Logo Southern California Edison (SCE) Logo Starbucks Coffee Logo Bank Of America Logo


Guardian National Security

Trained, BSIS-Licensed Security Guards


Expertly-Trained, BSIS-Licensed Security Guards

Superior Customer Care


Exceptional Customer Service Available 24/7

Competitive Pricing


We Match or Beat Any Competitor’s Quote

Reliable & Affordable Guard Services & Patrols to Help Altadena's Businesses & Communities Stay Safe

Even the best of communities are not immune to crime. Crime statistics for Altadena and surrounding areas show that planned crimes as well as crimes of opportunity are still a concern. In fact, a recent study showed that there were close to 40 violent crimes and almost 200 property crimes in Altadena over a six-month period. To help you combat this, our security guard and patrol services can be customized to effectively discourage criminals (such as shoplifters, vandals, robbers and burglars), control property access, protect guests at private events, ensure faster response in emergencies (such as fires) and more. Call us today and you will receive a customized security program that meets your goals, circumstances and budget in Altadena.

Private Security Services in San Marino, California

If you’re looking for private security services at your San Marino location, choose Guardian National Security. We’ll tailor our guard services to meet your short- or long-term security needs. Choose from standing security guards, mobile patrol services (on foot or bike or in a golf cart or vehicle), event security (crowd control, access control, bag check, etc.), private parking lot security guard services, transportation logistics/supply chain security, alarm monitoring and response, fire watch, close-of-business lock up and more. To better match your need in San Marino, our guards can arrive in a standard uniform or wear a modified uniform that is more appropriate for the assignment, such as a construction, casual or professional.

Guardian National Security - The Private Security Agency of Choice for Sierra Madre, CA Residents & Businesses

Hiring a licensed private security/patrol agency to protect your Sierra Madre business or community is a smart investment. That’s because a dedicated and well-trained security guard can monitor your Sierra Madre property for suspicious or out-of-the-ordinary activity, provide immediate response to activated alarms and deter criminals (especially those who prey on communities with low crimes rates and lax security procedures). Call us today to learn more.

What our

Clients Have to Say

Guardian National Security is committed to providing reliable, quality protection services to a variety of industries through custom-designed security strategies, expertly trained security guards, and excellent customer service.

Guardian National Security Services gave me so much peace of mind. They were able to secure my office building efficiently and professionally.

SAL A. Via Google

free consultations & quotes

Call Us Today to Book Standing Guards, Mobile Patrol Services, Event Security, Fire Watch & More

Call today and we’ll set up a time for you to receive a free, on-site estimate. We welcome requests for one-time, long-term, and short-term security guards, and work with clients to customize our guards’ appearance, duties, weapons (if any), and communication tools, such as two-way radios and cell phones. All client information is kept private and confidential and our guards are tracked using a GPS enabled app system.

Guardian National Security is a state licensed C7 contractor and a member of California Association of Licensed Security Agencies, Guards and Associates (CALSAGA). Our guards are all licensed by the California Bureau of Security and Investigative Services (BSIS).

Custom-Made, Personalized Security Plan

Guardian National Security | San Marino, Altadena, & Sierra Madre, California
Zip Codes: 91001, 91003, 91024, 91025, 91104, 91108, 91118
Area code: (626)