In maize breeding one of the most important roles belongs to selection of parents with good combining abilities. The data associated with combining ability and heritability of particular characters can be obtained from diallels. The main objective of this study was to evaluate the leaf area (LA) of 10 inbred lines and their F1 hybrids. Based on a diallel (without reciprocals) GCA and SCA were calculated. The components of the genetic variance were calculated using Griffing's (1956) method 2. The maximum LA value was determined for the combination L6xL10 (788.6 cm2), whereas the minimum for the combination L4xL5 (558.9 cm2). The average value of F1 generation was 678.8 cm2 and the variation range was from +109.8 cm2 to -119.9 cm2. Both, the GCA and SCA for LA were significant at p=0.01. The highest value of GCA was obtained for L2 (+31.33), whereas the lowest for L4 (-38.07). The highest value of SCA was determined for L6xL10 (+156.73). V žlahtnjenju rastlin igra eno od najpomembnejših vlog selekcija roditeljev z dobrimi kombinacijskimi sposobnostmi za želene lastnosti, ki jih običajno ugotavljamo z dialelnimi križanji. Namen raziskave je bil ugotoviti kombinacijsko sposobnost 10 samooplodnih linij koruze ter njihovih križancev za listno površino (LP). Na osnovi njihovih dialelnih križancev (brez recipročnih križancev) je bila za LP izračunana splošna (SKS) in posebna (PKS) kombinacijska sposobnost. Komponente genetske variabilnosti so bile računane po metodi 2 Griffingovega modela (1956) računanja kombinacijskih sposobnosti. Največja LP je bilaugotovljena za križanec L6xL10, (788,6 cm2), najmanjša pa za križanec L4xL5 (558,9 cm2), medtem ko je bila povprečna vrednost vseh križancev 678,8 cm2. Tako za SKS kot za PKS so bile ugotovljene statistično značilne razlike med križanci pri p=0,01. Največja vrednost SKS za LP je bila ugotovljena pri L2 (+31,33), najnižja pa pri L4 (−38,07), medtem ko je bila največja vrednost PKS ugotovljena za križanec L6xL10 (+156,73).