ABSTRACT Silicon nitride (Si 3 N 4 ) is reported to exhibit antibacterial properties and support osteoblast maturation, while polyetherketoneketone (PEKK) is considered to potentially have antibacterial and osseointegrative properties while offering favorable manufacturability through extrusion‐based additive manufacturing compared to traditional ceramics manufacturing. Incorporating silicon nitride into PEKK is hypothesized to enhance its bioactivity while maintaining processability, making Si 3 N 4 ‐PEKK composites promising for medical implants. Our objective was to determine optimal fused filament fabrication (FFF) parameters for PEKK and Si 3 N 4 ‐PEKK. Taguchi optimization (L9 array, n = 5) was performed on PEKK and 15 vol.% Si 3 N 4 ‐PEKK to assess the impact of printing parameters (layer height: 0.1, 0.2, and 0.3 mm; nozzle temperature (PEKK/Si 3 N 4 ‐PEKK): 340/380, 370/400, and 400/420; bed temperature: 130°C, 150°C, and 170°C; and chamber temperature: 110°C, 130°C, and 150°C) on ultimate tensile strength (UTS). Z‐directional tensile specimens were printed on a medical FFF printer. Specimens underwent tensile testing according to ASTM D638. Signal/noise ratios for UTS were calculated and ANOVA (Minitab 21.4.2) was used to assess statistical significance ( p < 0.05). Layer height had the greatest impact on UTS for both PEKK and Si 3 N 4 ‐PEKK. Optimal nozzle and chamber temperatures were 400°C and 130°C, respectively, while the optimal layer height was 0.1 mm for both materials. The optimal bed temperature for PEKK and Si 3 N 4 ‐PEKK was 150°C and 170°C, respectively. For PEKK, differences in all parameters were significant except for bed temperature, while for Si 3 N 4 ‐PEKK all parameters were significant except for nozzle temperature. The specimens with optimum statistically significant parameters showed the highest UTS for both PEKK (91 ± 2 MPa) and Si 3 N 4 ‐PEKK (76 ± 3 MPa). Layer height is the most influential printing variable for both PEKK and Si 3 N 4 ‐PEKK. The optimal PEKK printing condition has a comparable UTS, while Si 3 N 4 ‐PEKK achieved 84% of the injection‐molded value for neat PEKK.