It would depend on the type of party. For example, if the main activity of the party is drinking and dancing, then no. These behaviors promote our fallen flesh. But a birthday party or a celebration where people can fellowship about God and His word would be fine. Ask yourself, “Would Jesus attend this party?” We know he attended the wedding at Cana. (See John 2.)
Everything Jesus did glorified God. We need to copy our Lord’s example. 1 Corinthians 10:31, “Whether therefore ye eat, or drink, or whatsoever ye do, do all to the glory of God.”
It is very important to recognize that all believers do not always agree about what is or is not pleasing to God. In the early church, some Christians thought it was okay to eat meat offered to idols. They believed an idol was nothing and, apparently, the meat was economical. So, they purchased and ate it with a clear conscience. Other Christians were greatly offended by that practice. If they were to eat that meat, they would be violating their consciences. The Apostle Paul tells these dear ones to avoid that meat. He also encourages Christians not to offend fellow believers.
1 Corinthians 8:7-13 (NLT), “…Some are accustomed to thinking of idols as being real, so when they eat food that has been offered to idols, they think of it as the worship of real gods, and their weak consciences are violated….you must be careful so that your freedom does not cause others with a weaker conscience to stumble. For if others see you–with your "superior knowledge"–eating in the temple of an idol, won't they be encouraged to violate their conscience by eating food that has been offered to an idol? So because of your superior knowledge, a weak believer for whom Christ died will be destroyed. And when you sin against other believers by encouraging them to do something they believe is wrong, you are sinning against Christ. So if what I eat causes another believer to sin, I will never eat meat again as long as I live–for I don't want to cause another believer to stumble.”
Thus we see that we are always to keep our consciences pure.
So, should we tell others not to do something that offends us? It would be unwise to start dictating another’s behavior in matters where the Bible does not give specific directions. If the scriptures say something is a sin, that behavior is forbidden. But where the Bible gives us Christian liberty to decide these matters in our hearts, we should respect that person’s decisions. “Where the scriptures are wide, we are wide. Where the scriptures are narrow, we are narrow.”
Remember, “If possible, so far as it depends on you, live peaceably with all.” Romans 12:18 (ESV)