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Owing to their excellent mechanical and physical characteristics, superalloys are the most suitable material for use in hot sections of aircraft engines. Thousands of holes need to be drilled in constructive parts of machines, with laser technique emerging as the most effective. Laser drilling has been used to produce small diameter, accurately positioned holes, with little damage in regions around them, and in various materials. Effective laser employment of drilling of high quality holes for critical applications highly depends on correct selection and optimization of laser drilling parameters. In this work, the holes were drilled by a pulsed Nd3+:YAG laser, with maximum average power of 160 W, in superalloy Nimonic 263 sheets, thickness 0,7 mm and 1,2 mm. The holes were observed by optical and scanning electron microscope. Geometrical characteristics of laser drilled holes that depend on laser parameters were investigated and analysed. The aim of this investigation was to find optimal laser parameters which would produce as much as possible regular holes., Zbog svojih odličnih mehaničkih i fizikalnih značajki, superlegure su najpogodniji materijal za uporabu u toplim sekcijama zrakoplovnih motora. U konstrukcijskim dijelovima strojeva treba izbušiti tisuće rupa, za što se kao najučinkovitija pokazala laserska tehnika. Bušenje laserom koristi se za proizvodnju malih promjera, točno pozicioniranih rupa, s malim oštećenjima u području oko njih i u različitim materijalima. Učinkovita uporaba lasera za bušenje rupa visoke kvalitete za kritične primjene uvelike ovisi o ispravnom izboru i optimiranju parametara bušenja laserom. U ovom radu, rupe su izbušene Nd3+:YAG impulsnim laserom, uz maksimalnu prosječnu snagu od 160 W, u limovima superlegure nikla Nimonic 263, debljine 0,7 mm i 1,2 mm. Rupe su promatrane optičkim i skenirajućim elektronskim mikroskopom. Istražene su i analizirane geometrijske značajke laserski bušenih rupa, koje ovise o parametrima lasera. Cilj ovog istraživanja bio je pronaći optimalne parametre lasera koji bi omogućili što pravilnije rupe.