The Herald sampled some of the stores' fast-selling beauty products including perfume and concealer pens, which stand up well to better-known brands in every way especially in prices.
Lidl and Aldi have also invested in a body care range that is popular and cheaper than its competitors.
Described as the new Chanel No 5, Lidl's own specialised perfume, Suddenly Madame Glamour, comes in at just €3.49 per 50ml.
It boasts "citrus and floral notes, incorporating bergamot and jasmine"and was rated above Chanel's ¤89 Mademoiselle after a blind test. It is rivalling brands such as Daisy by Marc Jacobs, priced at €57.25 for a 50ml bottle, while Lady Million by Paco Rabanne is a costly €62.
When the Herald visited the Lidl store on Dublin's Cork Street, there was one bottle left. "Suddenly Madame Glamour is a new product that we introduced on a seasonal basis in late 2011 and it has performed very strongly," Caitriona McCarry of Lidl told the Herald.
"This year again it proved extremely popular and flew off the shelves." Lidl says the Cien and Iseree body care range are also top-sellers.
A 500ml bottle of Cien body lotion costs ¤1.79 compared with Dove at €2.99 for 250ml.
"The Cien Anti Wrinkle Night Cream Q10 Max was named 'Best Night Cream' by Reveal magazine UK last year," Ms Mc Carry added.
The pocket-friendly cream costs €1.99 for 50ml, while No 7's Perfect and Protect has a more expensive tag of €30.50.
Lidl's German rival Aldi's make-up range has also been turning heads. They are reporting strong sales of their Lacura beauty concealer pen which at €4.99 is far cheaper than the Yves Saint Laurent Touche Eclat Radiant Touch concealer pen at €30.
"The Lacura Beauty Concealer Pen has proven to be one of our most popular beauty lines," Aldi's group buying director Niall O'Connor said. "Our award-winning own brand Lacura beauty range offers an unrivalled combination of quality products at prices that can't be matched."
Aldi says its Irish-made Abbott & Broome care range is one of its strongest sellers with a 300ml shower gel costing just 59c. It has been likened to the popular Molton Brown gels that sell for around €22.