Host galaxy morphology studies of jetted narrow-line Seyfert 1 galaxies (NLS1) are scarce; so far only three of them have been investigated in detail. Though all three are hosted by late-type galaxies the sample size is too small to establish a preferred host galaxy type for jetted NLS1 sources; increasing the sample size is crucial to achieve statistically significant results. To this end we observed the host galaxies of nine NLS1 sources in near-infrared using NOTCam at the Nordic Optical Telescope. Seven of these sources are jetted based on the 37 GHz observations at Metsähovi Radio Observatory (see A. Lähteenmäki's talk). To determine the morphological types of the hosts we performed photometric decomposition of the near-infrared images using GALFIT. Here we present the results of the host galaxy modeling, discuss the importance of this study to our understanding of the nature of the diverse NLS1 population, as well as its significance and implications for active galactic nuclei research in general.