The presentc researchc projectc was conductedc in the Cerealc Cropc Researchc Institutec (CCRIc) Pircsabak, Nowshehrac (K.P) Pakistanc duringc summerc 2014. Six maizec (Zea mays L.) genotypesc werec used in the researchc experimentc viz; PSEV-3, Azamc, Sarhadcwhite, Jalal, Iqbalc and Paharic. The maizec genotypesc were crossedc in a completec 6x6 diallelc fashionc and theirc Fc1 generationc was studiedc. Meanc squaresc due to GCA and SCA were highly significant for all the traits in F1 and F2 generations with the exception of GCA values for Leaf Area (cm) and Moisturec % in F1 and F2. The combiningcability analysescalso revealedc that majorityc of the traitscwere controlledc by partialc dominancec with additivec genec action. In F1generationc, the highest SCAc effects were manifestedc by crossesc involving PSEV-3 i.e PSEV-3x Iqbal, PSEV-3xAzam, PSEV-3 x Sarhadc White PSEV-3 x Pahari Azam x Pahari and Azamc xIqbal. Cultivar PSEVc3 of the abovec genotypesc provedc to be the best generalc combinerc as mentionedc earlier havingc highestc GCA valuesc producedc best specificc crosses. In case of F2 generationc maximumc SCA were exhibitedc by Sarhad WhitecxIqbal and JalalcxIqbal were the best crossc combinationsc. The cultivar Sarhadc White having negativec GCAc affectsc for ninec charactersc, therefore it was concludedc that comparativelyc low x highc parentsc performedc well in SCAc determinationc. Heterosisc of varyingc magnitudec was foundc in F1 and F2c generationsc. Mid parentc heterosisc was morec pronouncedc than batterc parentc heterosisc. Yieldc and its componentsc showedc maximumc heterosisc while otherc traits showedc lowc to moderatec heterosisc. Onc the basisc of heritabilityc, GCA, SCcA and heterosisc the genotypesc PSEV-c3 x Sarhadc Whitec, Sarhadc Whitec x PSEV-c3, PSEV-c3 x Paharic, PaharixPSEV-3, Sarhad White x Iqbalc andc Iqbalc x Sarhadc White were foundc promisingc. These competitivec genotypesc had a greatc potentialc to becomec vigorc withc highc yield and bestc suitedc for generalc cultivationc. In biochemicalc studies, parentalc cross of maizec genotypesc in whichc prolinec contentsc mostlyc increased in Iqbalc which rangedc uptco 0.37 (μmol/g) andc decreasedc in Azam with 0.08 (μmol/gc). The highestc levelc of prolinec contentsc showsc in Azamc x Sarhad x White which ranged 0.28 (μmol/g) and the lowest ranged was exhibited 0.06 (μmol/g) in PSEV-3 Iqbal in reciprocal crosses. Directccross of maize genotypes presented highest level of prolinecconcentration which was 0.35 (μmol/g) in Iqbal x Sarhad White and the lowestcconcentration was 0.08 (μmol/g) in Jalal x Azam. In molecularcstudy the SSR markers were used to estimate the genetic diversity, polymorphiccinformation content and number of alleles. In the present study maize genotypes exhibited various levels of genetic polymorphism by SSR markers. In present research project eight genotypes shown high genetic diversity as compared to other genotypes. Which are Pahari × Sarhad White, Pahari × Azamc, Sarhad White × Jalal, Jalal × Sarhad White, Sarhad White × Azam, Sarhad × Iqbal, Jalal × PSEV-3 and Iqbal × Sarhad White. Geneticcdiversity in maizecgenotypes gives the opportunity of best results for future breeding programs.