<p>This study aimed to compare the effects of wearing KF94 2D and 3D face masks on cardiopulmonary function and subjective sensations during graded exercise in adult males. This crossover study initially categorized 12 adult males into a group wearing a 2D face mask (experimental group) and the same group wearing a 3D face mask (control group) following a washout period. The application of KF94 masks was of two brands—Ibanari(2D) and Good Vibes(3D)--approved by the Food and Drug Administration of Sb Global Healthcare Co., Ltd. Li et al.’s questionnaire (2015) was used to observe changes in cardiorespiratory function (SBP, DBP, Rf, VT, VE, VO2, FiO2) of study participants who underwent a graded exercise test. The subjective discomfort from wearing a face mask during exercise was assessed. There was no significant difference in Rf, VT, VE, VO2, FiO2, and exercise end time when the 2D and 3D masks were worn during cardiorespiratory function and maximal exercise (<i>p</i> &gt; 0.05), but when the 2D mask was worn, VO2 value was high (<i>p</i> &lt; 0.05). However, from VO2 to the six-minute point of exercise, 2D was significantly higher than 3D group (<i>p</i> &lt; 0.05). Subjective sensation immediately after maximal exercise was higher in respiratory resistance immediately after exercise in the 2D (6.29 ± 2.4 points) than in the 3D group (4.16 ± 3.0 points) (<i>p</i> &lt; 0.05). We concluded that the design type features of the 2D and 3D face masks are not significantly affected by filtration efficacy and breathability during maximum exercise in the otherwise healthy adult male participants.</p>