Taylor, who was played to her second All-Star game on Sunday, collected seven rebounds, six steals and three assists. She is averaging 24.8 points through her last nine games.
The Mercury pulled away in the third quarter behind a commanding 19-4 run capped by Taylor's three-pointer that made it 64-45 at the 5:20 mark.
Seattle opened the game on fire, hitting seven of 11 shots to create an early 19-6 advantage with 4:50 remaining in the first quarter.
However, Phoenix responded with an impressive 16-0 surge to take the lead for good, 22-19. Taylor netted nine points during the run.
Kelly Miller and Tangela Smith each scored 10 points for Phoenix, who shot 46% (34 of 73) from the field and improved to 9-3 against Western Conference opponents.
League-leading scorer Lauren Jackson had 33 points and 11 rebounds and Betty Lennox scored 22 for Seattle, who have lost three of their last four games.
Elsewhere on Tuesday, All-Star Katie Douglas scored 22 points as the Connecticut Sun posted an 84-79 victory over the Minnesota Lynx.
Lindsay Whalen scored 20 points and handed out four assists and All-Star Asjha Jones added eight points and two blocks for Connecticut (10-11), who have won four straight.
The Sun have also won five of six against the Lynx to tie the all-time series at 8-8.
Minnesota have lost seven straight games to tie a season high - they started the season 0-7.
With the score tied at 66-66 following a lay-up by Minnesota All-Star Seimone Augustus with 5:48 remaining, Connecticut went on a 14-4 run to put the game away. Douglas hit a three-pointer to begin the spurt and Whalen's free throw with 2:44 left made it 80-70.
Douglas connected on eight of 16 from the floor and Whalen made seven of nine from the field for the Sun, who shot 43% (21 of 73).
Augustus scored 24 points and Svetlana Abrosimova added 17 points and five assists for the Lynx (5-17), who shot 41% (30 of 73) and have the worst record in the WNBA.
Finally, Becky Hammon scored 25 points and dished out six assists to lead the San Antonio Silver Stars to a 63-61 win over the Los Angeles Sparks.
Hammon hit a three-pointer with 1:28 remaining to give the Silver Stars a 61-59 advantage. After Tameka Johnson's running jump-shot tied the game for Los
Angeles, Sophia Young made a lay-up to give San Antonio a lead with 17 ticks left that they would not relinquish.
Sidney Spencer, who had 10 points, missed a jump-shot in the final seconds which would have tied the game for the Sparks, who shot just 39% (25 of 64) from the field.
Young scored 17 points and grabbed five rebounds for the Silver Stars, who have won five straight games and nine of their last 11.
Taj McWilliams-Franklin had 14 points and Sherill Baker added 10 for Los Angeles, who have lost seven in a row.