To prepare hydroxyapatite (HA)/poly(vinyl alcohol) (PVA) composite fibers with high processibility applicable to various biomedical fields, HA/PVA composite powders were synthesized through a coprecipitation method and then mixed with pure PVA in dimethyl sulfoxide at 90 degrees C for 2 h to prepare wet-spinning dopes. HA/PVA solutions with HA contents of 0, 1, 3, 5, 10, and 15 wt % were analyzed with a rheometer to elucidate the effect of HA particles on the shear viscosities of the spinning dopes. The spinning dopes with pure PVA and an HA/PVA concentration of 12 wt % showed non-Newtonian flow behaviors, and as the HA content increased from I to 15 wt %, the shear viscosities increased simultaneously because of the complex formation between PVA chains, citric acid, and HA particles acting as crosslinkers. The increased viscosities of the spinning dopes diminished the breakage of PVA fibers and enhanced the spinnability. Through the addition of citric acid interacting with both PVA and HA particles, the aggregation of HA particles was suppressed, and it was possible to prepare HA/PVA composite fibers with smooth surfaces. An adequate amount of HA in the PVA fibers improved the thermal and mechanical properties of the fibers because uniformly dispersed HA particles interacting with PVA chains through hydrogen bonding in the PVA matrix complemented the structural defects. (c) 2007 Wiley Periodicals, Inc.