The spinnable carbon nanotubes (CNTs) that form sheets by directly spinning from its substrate show unique properties and promise applications in diverse fields. For conventional chemical vapor deposition (CVD) methods, helium (He) and argon (Ar) gases are used as the carrier gas that sets inert environments. However, neither of these are considered inexpensive for the mass-production of CNTs. In this paper, we report a successfully synthesized spinnable CNT forest in a nitrogen (N2) environment, a chemically stable and inexpensive gas. Fine-tuning of iron (Fe) catalyst allowed for an optimal condition for the growth of spinnable CNT forest. Catalyst particle analysis and the CNT forest structures are studied via AFM and SEM, and nanostructure are studied by TEM. Also, for the comparison, CNTs grown in He is also studied as a reference. We believe this study can help to step further for mass production of CNT applications.