Van Beijnen's contract runs through to 2021, with the 20-year-old's deal including a €100 million (£89m/$113m) buyout clause.
He arrives on a free transfer from NAC Breda and will link up with Barcelona B for the 2019-20 season.
Van Beijnen, who also spent time with Eredivisie giants PSV and Willem II, is the son of Frenkie de Jong's agent Ali Dursun.
The 22-year-old midfielder is preparing for his first pre-season with Ernesto Valverde's side.
Van Beijnen will be hoping to join a fellow countryman in the first-team ranks at some stage.
For now, though, he will be eased into the fold by those in Catalunya.
🔵🔴📝 We are delighted to announce that 20 year old Dutch defender Mike van Beijnen has signed a 2-year contract to join @FCBarcelonaB as a free agent.— FC Barcelona (@FCBarcelona) June 20, 2019
📋 Full details here: 👉 https://t.co/wFQXfdrmdX pic.twitter.com/ICaEeuQFGT
Revealing the deal on the club's official website , Barca said in a statement: "Mike van Beijnen signed his contract with FC Barcelona this Thursday afternoon at the Ciutat Esportiva training ground in the presence of director Silvio Elías, head of professional youth football, together with Josep Segura, sports manager for football, and José Mari Bakero and Guillermo Amor, who are in charge of the youth setup at the club.
"The right back, who has previously played for NAC Breda, PSV Eindhoven and Willem IIput pen to paper for the next two seasons, though to 2021. He arrives as a free agent and his buyout clause has been set at 100 million euros.
"He successfully passed the routine medical checks with the club medical services."
There is the promise of more transfer business to come at Barca.
A number of high-profile figures continue to be linked with the club during the summer transfer window.
It is expected that another forward will arrive at some stage, with possible deals for the likes of Atletico Madrid striker Antoine Griezmann and Paris Saint-Germain superstar Neymar being mooted .
Any approach for the latter would see him returned to Camp Nou two years are making a record-breaking switch to France.