The plans also include the introduction of a Costa Coffee in the arrivals hall and departure lounge as well as the expansion of the executive lounge with additional seating.
Work on the investment will start later this month and will be completed in time for next summer.
The investment plans for the terminal also include increased retail space, allowing for a larger WH Smith store, upgrading the hold baggage screening system to meet enhanced security requirements, and the opening of additional seating areas in the departure lounge.
The car parking facilities will also see an investment with a new ‘meet & greet’ car parking for customers with a dedicated area for drop off and pick up close to the terminal building.
A new car hire centre will also be introduced close to the terminal building.
Chief executive of the Welsh Government-owned airport, Debra Barber, said: “We are delighted to share our plans for the airport development as it shows our commitment to achieving our vision of being an outstanding capital city airport delivering an exceptional customer experience.
“We have achieved a huge amount over the last few years and improved the experience for our customers but know there is still much more we can do to ensure we exceed expectations.
“The latest investment will significantly transform the experience for customers, offering more choice and quality in modern, welcoming surroundings.
“This is especially important at a time when we are experiencing passenger growth and working with our airline partners to introduce more choice in services for our customers.
“We look forward to the projects being completed over the coming months and our customers enjoying the new facilities next summer.”
The airport currently handles 1.4 million passengers a year.