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Antimicrobial resistance (AMR) in bacteria is a major public health concern in the US and around the world. <i>Campylobacter</i> is an important foodborne pathogen that resides in the gut of pigs and is shed in feces, with the potential to be transmitted to humans. In pigs, the oral route, either in-feed or in-water, is by far the most common route of administration of antimicrobials. Because the distribution of the antibiotic in the gut and the dosages are different, the impact of in-feed vs. in-water administration of antibiotics on the development of AMR is likely to be different. Therefore, a study was conducted to compare in-feed vs. in-water administrations of chlortetracycline (CTC) and/or tiamulin on fecal prevalence and AMR profiles of <i>Campylobacter</i> among weaned nursery piglets. A total of 1,296 weaned piglets, allocated into 48 pens (27 piglets per pen), were assigned randomly to six treatment groups: Control (no antibiotic), in-feed CTC, in-water CTC, in-feed tiamulin, in-water tiamulin, or in-feed CTC and tiamulin. Fecal samples were collected randomly from 5 piglets from each pen during the pre-treatment (days 0, 7), treatment (days 14, 21), and post-treatment (days 28, 35) phases. Bacterial isolations and species identifications were conducted by culture and PCR, respectively. The microbroth dilution method with Sensititre^TM plates was used to determine the antimicrobial susceptibility and resistance of <i>Campylobacter</i> isolates. The results on resistance were interpreted based on the European Committee on Antimicrobial Susceptibility Testing (EUCAST) epidemiological cutoff values for <i>Campylobacter</i>. The overall prevalence of <i>Campylobacter</i> was 18.2% (262/1440). Speciation of <i>Campylobacter</i> isolates by PCR indicated the prevalence of only two species: <i>Campylobacter hyointestinalis</i> (17.9%; 258/1440) and <i>C. coli</i> (0.3%; 4/1440). <i>Campylobacter</i> isolates were resistant to tetracycline (98.5%), ciprofloxacin (89.3%), and nalidixic acid (60.3%). Neither the antibiotic nor the route of administration had an effect (<i>p</i> > 0.05) on the prevalence of AMR <i>Campylobacter</i> in the feces of piglets.