Guido Andreozzi and Miguel Ángel Reyes-Varela won the doubles title at the 2024 Croatia Open Umag, defeating Manuel Guinard and Grégoire Jacq in the final, 6–4, 6–2.

Blaž Rola and Nino Serdarušić were the defending champions,^[1] but lost in the first round to Sander Arends and Denys Molchanov.

	First round							Quarterfinals							Semifinals							Final
	1	Y Bhambri A Olivetti	6	6
		J Kovalík C Ugo Carabelli	3	2				1	Y Bhambri A Olivetti	4	6	[6]
		M Guinard G Jacq	77	6					M Guinard G Jacq	6	1	[10]
		M Bortolotti MC Romios	63	3												M Guinard G Jacq	7	6
	3	N Barrientos F Cabral	6	3	[12]											F Romboli M Zormann	5	2
		R Jebavý T Macháč	3	6	[10]			3	N Barrientos F Cabral	3	4
		LD Martínez C Rodríguez	3	6	[4]				F Romboli M Zormann	6	6
		F Romboli M Zormann	6	3	[10]																		M Guinard G Jacq	4	2
	WC	K Kajin D Žmak	4	4																		4	G Andreozzi MÁ Reyes-Varela	6	6
		J Eysseric O Luz	6	6					J Eysseric O Luz	6	67	[10]
		A Chandrasekar A Kadhe	2	2				4	G Andreozzi MÁ Reyes-Varela	2	79	[12]
	4	G Andreozzi MÁ Reyes-Varela	6	6											4	G Andreozzi MÁ Reyes-Varela	6	6
	WC	B Rola N Serdarušić	2	4												S Arends D Molchanov	4	3
		S Arends D Molchanov	6	6					S Arends D Molchanov	6	7
		J Schnaitter M Wallner	6	6					J Schnaitter M Wallner	4	5
	2	T Arribagé S Doumbia	4	3

• Main draw